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List of vacuum tubes

The tuned fork beyond wikipediA

This is a list of vacuum tubes or thermionic valves, and low-pressure gas-filled tubes, or discharge tubes. Before the advent of semiconductor devices, thousands of tube types were used in consumer electronics – most of them to amplify AF, IF and RF signals in TV sets and AM/FM radios; some are still in production today for valve audio amplifiers – but many industrial, military or otherwise professional tubes were also produced, many of these highly specialized; only a few types of those are still used today, mainly in high-power RF/microwave (VLF, LF/LW, MF/MW, HF/SW, VHF low/mid/high, UHF low/high, SHF, EHF, THF) applications.

Tube characteristics

Heater or filament ratings

The Tungsten that tube heaters are usually made of, exhibits a positive temperature coefficient of resistance, meaning the cold resistance is much lower than the hot resistance, causing a considerable inrush current when powering up a device.

Vacuum tubes fall into three mainly non-interchangeable categories regarding their heater or filament voltage/current,[1] though some tubes' heaters run at both a standardized voltage and current, e.g., 6.3 V at 300 mA or 13 V at 200 mA, making them suitable for either series or parallel operation.

  1. Battery types, ubiquitous before the 1930s but since then only for mobile/portable equipment; all filaments in a device are connected in parallel and rated the same voltage. Early sets had the heaters connected to the battery via a variable filament resistor (rheostat), later via an automatic ballast tube, to compensate for the decreasing battery voltage.
    Types for hand-held/portable devices are usually 1 to 2 V directly heated, to save heating power (therefore requiring a DC current), except if the (due to the voltage gradient along the filament) poorly defined cathode potential impedes the function of the tube, as is the case e.g. with AM detector diodes with filament voltages of 1.9 V or more; in such cases, indirect heaters were employed and marketed as equipotential or unipotential cathode at the time.
    Types for mobile devices (installed in land/marine/aerial vehicles) are indirectly heated from the 6-, 12-, or 24-volts engine crank battery resp. the alternator or APU; a high-output radio alternator option to meet the additional power demand, was offered for cars (not to be confused with the Alexanderson alternator).
    • 5 V, directly heated, via a rheostat (used in home radios; examples)
    • 12.6 V, indirectly heated, from six lead-acid cells (used in 12-volts vehicle equipment; examples)
    • 26.5 V, indirectly heated, from twelve lead-acid cells, used in 24-volts vehicle equipment, also on the standard avionics 28-volts DC bus
  2. Types for AC-only equipment with a mains transformer; dull-emitter signal and low-power tubes are indirectly heated (except for some 1920s power tubes and rectifiers) and all heaters in a device are rated the same voltage and fed in parallel from a transformer secondary winding.
    In North America, a 2.5VRMS standard was used 1929–34 (examples); elsewhere, nominal heater voltages from 1920's lead-acid/"battery eliminator" era (multiples of 2 or 2.1V) were kept, 4VRMS in the UK (examples),[1] but since the 1940s the 6.3-volts and 12.6-volts car radio standards prevailed everywhere; 5VRMS became a standard for full-wave rectifiers (examples) fed from a separate transformer winding because their filament/cathode is on anode supply potential.
    • However, most RF power tubes are bright-emitter directly heated, so for the abovementioned reason, the heater voltage must be much smaller than the signal voltage on the control grid and is therefore in the 1.1 to 25 V range, drawing up to hundreds of Amperes from a suitable heater transformer capable of slowly ramping up the heater voltage to smooth out the otherwise destructive heater inrush current, and to minimize thermal stress to the vacuum seals, when powering up.
      Some high-power RF tubes have a 2-phase (Eimac 8974, RCA 891 and Philips TAW12/10) or 3-phase (RCA 893, 898 and Philips TAW12/35G, TBW15/125) heater to reduce hum.
      Some microwave power tubes require heater voltage derating above a specified maximum operating frequency where electron transit time effects start causing back bombardment heating of the cathode.
  3. Types for mass-produced radio and TV receivers designed to run on either AC or DC mains power (ac/dc) with no mains transformer; they are always indirectly heated and all heaters are connected in series across the mains power supply, possibly with an additional ballast resistor or barretter chosen such that the sum of the heater and ballast voltages equals the mains voltage; all tubes in a device need to:
    • be rated the same heater current, typically 50, 100, 150, 200, 300, 450 or 600 mA, depending on mains voltage and device tube count
    • have the same warm-up time constant, typically 11 seconds, controlled by increasing the cathode's thermal capacity so it wouldn't overheat when powering up
    • have a heater/cathode insulation that withstands the high voltage at the top of a series heater string, which some tubes intended for parallel heater operation can't; if a heater further down the string breaks, they even have to withstand the full mains voltage
Some power tubes have a heater tap near one end to feed a small pilot lamp, thus shunting away from it the heater inrush current when powering up.[6]
Typical parallel and series heater ratings
P/I 150mA 300mA 450mA 600mA
945mW 6.3V 3.15V 2.1V 1.575V
1.89W 12.6V 6.3V 4.2V 3.15V
2.835W 18.9V 9.45V 6.3V 4.725V
3.78W 25.2V 12.6V 8.4V 6.3V

The currents drawn by parallel-connected types, and the voltages across series-connected types, vary widely according to the tube's heating power requirements. Otherwise identical tubes were manufactured in several variants with different heater ratings, but usually the same heater power[10]

Some tubes feature a center-tapped filament/heater, providing:

  1. Two voltage/current options by series resp. parallel wiring of their two heater sections, e.g. 2×6.3 V/150 mA (series) resp. 6.3 V/2×150 mA (parallel) (useful in dual-system (6-volts and 12-volts) car radios; examples), or
  2. A defined cathode current return path and reference point for directly heated tubes where signal ground, and an internal shield and/or a suppressor grid if present, are connected to; this is the only allowed use for many directly heated high-power RF tubes since their center-tap can't carry the huge heater current, except with 2-phase heater tubes

In this list, Filament implies a directly heated tube; Heater implies an indirectly or half-indirectly heated tube - in half-indirectly heated tubes, the cathode sleeve and one side or the center-tap of the filament share the same pin.

Signal tube grids

Typical mixer tube grid topologies
Grid# Hexode British Heptode American Heptode Octode
Oscillator
input
3 1 1 1
Oscillator
helix anode
n/a 2 n/a 2
Screen 2&4 3&5 2&4 3&5
Signal input 1 4 3 4
Suppressor n/a n/a 5 6
  • Dual-control pentode: The suppressor grid has a short grid base (=fine pitch) like the control grid and is available on a separate base pin (instead of internally tied to the cathode) so it can be used as a second control grid; anode current flows only if neither grid is negative; derived from the dual-grid mixer triode and precursor of the Gated-beam discriminator and hexode/heptode/octode/nonode approaches
  • Helix with a constant pitch: "High-slope" = low/medium/high-μ /ˈmj/ = sharp-cutoff tube, for use in fixed-gain amplifiers
  • Helix with a variable pitch: "Super-control" = Variable mutual conductance = Vari-μ = remote or semiremote-cutoff tube, for use in variable-gain amplifiers where the gain-control voltage is applied as control grid bias
    Note: Gain (amplification factor) μ = Mutual conductance gm × Anode resistance Ra
  • Strap frame-grid: While a normal grid is a thin wire wound to a helix around two swaged metal posts, a frame-grid is a thin wire wrapped around a rectangular stamped sheet metal frame; except in planar microwave tubes, one such frame on either side of the cathode is needed to form a grid
  • Shadow-grid: Beam pentode with a beam-forming extra grid between control and screen grids (technically a beam hexode), aligned to cast an electron shadow on the screen grid wire and thus reduce screen grid current and hence anode/screen grid distribution noise

Power tube anodes

The anodes of high-power tubes are usually made from Copper because of its high electrical and thermal conductivity.[11] Their maximum power dissipation can be exceeded for a short time, as long as the average is not exceeded over the anode's thermal time constant (typically 0.1 sec). In Class-C applications, the amplifier output power delivered to the load may be higher than the device dissipation. [Im]pulse-rated anodes are optimized for anode voltage surges and heat-up time constant, compared to their CW-rated counterparts.[12]

Due to dielectric losses, tube efficiency decreases with increasing operating frequency; the maximum anode voltage is therefore derated above a specified maximum frequency, which in turn reduces the available output power.[13]: 143  Usual cooling methods are:

Internal anode:

  • Natural convection: Air moves freely along the tube; modest power levels only
  • Radiation: The (at maximum anode power) orange-red glowing anode, made from Graphite or from a high-work function refractory metal such as Molybdenum or Tantalum, optionally Zirconium-coated ("Pyrovac"), dissipates heat by its infrared radiation through the envelope, which in the case of high-power tubes, is made from an infrared-transparent hard glass (softening point ≥750 °C) such as Silica. The vacuum seals may still need forced-air cooling through special ventilated (=blow-through) bases such as the B4A or the B8F Eimac/JEDEC B8-236

External anode protruding through the envelope so a good electrical and thermal contact can be made:

  • Liquid convection: Uses convection and gravity alone for pumping the coolant, modest power levels only; the heat sink sits atop the tube
  • Jacket: A liquid coolant is pumped through an outer metal jacket thermically connected to the external anode
  • Helix: A liquid coolant is pumped through a helix tube welded around the external anode
  • Water/vapor ("Multiphase"): The external anode is immersed in evaporating water, and the steam is collected, condensed and recycled

Bases

Drawings below; most bases are made of phenolic resin (Bakelite) or of pressed glass ("all-glass"); RF tube bases requiring low dielectric loss or high breakdown voltage use porcelain/ceramics or Steatite (Isolantite) or ground mica-filled resin (Micanol)[14]

Relevant standards include:

Media related to Vacuum tube bases at Wikimedia Commons

—Awaiting upload of suitable images there:

  • Flat-Press Pencil subminiature bases with 2/3/4/5/6/7 wire-ends
  • Round Pencil subminiature bases with 5/8 wire-ends
  • B4A Ventilated 4-pin base
  • B4B Midget 4-pin Hivac subminiature base
  • B5D/U5G (Medium shell), B5E (medium metal shell), B5F (all-glass) Giant 5-pin, B5K Supergiant 5-pin UY bases with Bayonet
  • B7D/U7G Giant 7-pin base with Bayonet
  • UV-type base with stubs
  • Peanut base with stubs
  • 4-pin and B3A 3-pin PeeWee bases

Envelopes

—Awaiting upload of suitable images to Commons:

  • Single low-frequency Pencil subminiature tube
  • Upright Lighthouse tube
  • Microwave Micropup-type disk-seal coaxial tube
  • Oil can tube
  • Microwave Pencil-type disk-seal coaxial tube
  • Microwave Rocket-type disk-seal coaxial tube
  • OCP7x next to a DF64

Special quality tubes

Premium/SQ tubes for professional/industrial/computer/telecommunications purposes featured some modifications including:

  • Long-life design
  • Tightened specifications
  • Gold-plated base pins to prevent corrosion and, especially during the 400...600 °C bake-out, entry of Hydrogen into the Cunife or Fernico (Kovar) base material
  • Gold-plated grid wires to prevent secondary emission
  • Tightly twisted pair filament inside the cathode sleeve to reduce hum pickup from the AC heater supply
  • Silicon-free Tungsten filament to prevent cathode interface/poisoning after prolonged periods in cut-off (required in digital circuitry and in hot spares)
  • Improved Alumina insulation between the heater and cathode sleeve so the cathode could be elevated to a higher voltage above the heater supply
    Note that a cathode positive to the heater was less detrimental to the oxide insulation between heater and cathode than the reverse, helping to prevent pyrometallurgical electrolytic reactions where the oxide touches the Nickel cathode, that could form conductive Aluminium tungstate and which could ultimately develop into a heater/cathode short-circuit
  • No getter to minimize internal leakage currents via getter material condensed on the inside walls of electrometer tubes
  • Dual getters to maintain a better vacuum
  • Ruggedized (more rigid) electrode supports to reduce microphonics and improve mechanical shock and vibration resistance
  • Mica spacers without sharp protrusions which could flake off and become loose inside the envelope, possibly lodging between the grids and thus changing the characteristics of the tube
  • Constricted envelope section to firmly hold specially shaped flakeless mica spacers in place (5920/E90CC, 6084/E80F, 6922/E88CC)

Numbering systems

North American systems

Standardizing bodies were:

  • RMA – Radio Manufacturers Association (1924)
  • RTMA – Radio-Television Manufacturers Association (1950)
  • RETMA – Radio Electronics Television Manufacturers Association (1953)
  • EIAElectronic Industries Association (1957)

RETMA standard tubes system

In use since 1933 on the RMA Electron Tube Registration List, now known as the RETMA system

  • A number ("prefix") with up to 3 digits: Filament/heater voltage rounded .6 down to a whole number; 0 indicates a cold-cathode tube. Tubes with a center-tapped filament/heater are assigned the higher voltage option
    Exceptions include 2 volts DC filament tubes; 5-prefix series heater tubes, which go up to 5.9 volts (5U9/LCF201, 5X9/LCF200) to avoid cluttering the 6-prefix; 7-prefix and 14-prefix Loctal tubes; 2.5-volts 3B4/DL98; 11.6-volts 10GV8/LCL85[18]
  • Up to 2 sequentially assigned letters, skipping the letters I and O and starting amplifier tubes from the letter A, working forward through the alphabet, while starting rectifier tubes from the letter Z, working backwards; since the two met (first the numerous 6-prefix, low elements-count tubes c. 1937), the single-letter namespace became exhausted, so combinations like AB, AC, AD, AE... were used, avoiding same-letter repetitions, reserving those ending in P for CRTs (see below) and henceforth assigning rectifiers also in forward-order
    Wherever possible, different-heater versions retained the original's letter combination; exceptions include: the 12BR7 and 9BR7 are unrelated to the 6BR7; the series heater versions of the 6.3 V/450 mA 6BL8/ECF80 are the 9.0-volts 9A8/PCF80 for 300mA strings, the 6.0-volts (thus requiring a different letter combination) 6LN8/LCF80 with controlled warm-up for 450mA strings, and the 4.6-volts 4BL8/XCF80 for 600mA strings
    The development of new tubes ended with the combination MY, although already by the end of the one-letter era, when the control grid top cap was discontinued and replaced by a regular base pin ("single-ended tube" - all connections on one end; not to be confused with the single-ended amplifier circuit), so-modified existing tubes, and the first new ones thereafter, were marked with a preceding letter S (6F5/12F5 → 6SF5/12SF5, 6K7/12K7 → 6SK7/12SK7, 1SA6-GT, 1SB6-GT, 6SB7Y, 6SC7/12SC7, 6SL7-G, 6SU7-GTY).[16] Similarly in the 1940s, 1.4 volt DC filament tubes (and the 2.8 volts center-tapped 3LE4, 3LF4) with a Loctal base were marked with a preceding letter L; 6.3- resp. 12.6-volts Loctal tubes were all assigned the prefixes 7 resp. 14 instead of 6 resp. 12, except 12B7 (=14A7)
  • A number with up to 2 digits: Count of active elements, including any shield and the heater in indirectly heated tubes – internally connected elements count as one; the use is somewhat arbitrary:
  • 1 – Directly heated half-wave rectifier; ballast tube/resistor; barretter
  • 2 – Half-wave rectifier; voltage-regulator tube; ballast tube with a lockout jumper; barretter with a filament tap for pilot lamp(s)
  • 3 – Hot- or cold-cathode rectifier; voltage-regulator tube; directly heated triode
  • 4 – Hot- or cold-cathode rectifier; cold-cathode trigger tube; directly or indirectly heated triode or pentode; indirectly heated triode thyratron
  • 5 – Indirectly heated full-wave rectifier; separate cathodes dual diode; triode; tetrode; Shadow-grid beam pentode/hexode; Triple-Twin; tuning indicator; indirectly heated triode thyratron; cold-cathode trigger tube
  • 6 – Separate cathodes dual rectifier; tetrode; pentode; heptode (pentagrid converter); common cathode dual triode; common cathode dual diode + triode; separate cathodes dual diode; common cathode quad diode; tuning indicator; Triple-Twin; Sutton tube (=Reflex Klystron)
  • 7 – Separate cathodes dual rectifier with a heater tap for a pilot lamp; pentode; heptode; Nonode; triode/hexode mixer; dual triode; common cathode triode + pentode; dual diode + pentode; dual diode + triode; diode + split-anode tetrode; common cathode dual pentode; separate cathodes triple diode; common cathode quad diode; tuning indicator
  • 8 – Heptode; octode; triode/hexode mixer; dual or triple diode + triode; common cathode (dual) diode + pentode; separate cathodes dual triode; separate cathodes triode + tetrode; triple triode; diode + triple-anode tetrode; split-anode pentode; triode + pentode; quad diode; common cathode sextuple diode; beam deflection tube
  • 9 – Separate cathodes dual diode + pentode; separate cathodes triode + pentode; common cathode dual triode + pentode; triple triode; separate cathodes dual pentode
  • 10 – Separate cathodes triple triode; separate cathodes dual pentode; dual diode + dual triode
  • 11 (Compactron limit) – Separate cathodes dual triode + pentode; separate cathodes triode + dual pentode; separate cathodes dual diode + dual triode; separate cathodes dual pentode
Exceptions include the 6L6-G/GT, 12L6-GT, 25L6-G/GT, 35L6-GT and 50L6-GT with a glass envelope and 5 elements, but legacy-named after the original 6L6 and 25L6 with a metal envelope connected to pin 1, making the sixth element
  • Optionally, a possible dash ("-") followed by a suffix of up to three Latin letters: Upgrades to the original model or different envelope outlines; the use is somewhat arbitrary:
  • A, B, C – Upgraded, backward-compatible drop-in replacements
  • E – Export version
  • G – Shouldered glass envelope, ST-12 to ST-16 size
  • GTGlass Tubular cylindrical envelope, T-9 size
  • GT/G – Glass envelope, T-9 size interchangeable with G and GT types
  • L – Loctal base
  • LM – Metal envelope with an Octalox (=Loctal) base
  • LT – Glass tubular envelope with an Octalox base
  • M – Metal envelope with an Octal base
  • MG – Metal-glass tube, a glass envelope hidden inside a tightly fitting metal jacket to make it look like a metal envelope
  • ML – Metal envelope with a Loctal base
  • S – Metal particles spray-shielded glass envelope
  • W – Ruggedized, or avionics/industrial/military grade (phased out since 1942 in favor of the RMA and EIA systems)
  • WA, WB – Upgraded, backward-compatible drop-in replacements
  • XLow loss ceramic base for improved RF performance
  • Y – Low loss Micanol base for improved RF performance
  • Optionally, manufacturers may decide to combine two designations into a single one, such as 6DX8/ECL84 (6DX8 and ECL84 being identical tubes under different naming schemes); 3A3/3B2 (drop-in replacement 3B2 superseding 3A3); 6AC5-GT/6AC5-G (6AC5-GT superseding 6AC5-G); 6BC5/6CE5 (6BC5 and 6CE5 being sufficiently identical)

Ballast tubes/resistors and barretters were assigned the following subset:

  • <Voltage>A1 to <Voltage>Z1 – No filament tap, no jumper
  • <Voltage>A2 – Filament tap for two pilot lamps
  • <Voltage>B2 – Filament tap for one pilot lamp
  • 1D2, 1E2 – With a jumper to unpower the device when the ballast is pulled from its socket

For examples see below

Cathode-ray tubes:

  • The first number gives the screen diagonal or diameter in inches (instead of the heater voltage)
  • One or two sequentially assigned letters
  • The last number is preceded by a P and specifies the Phosphor used

Examples:

  • 1EP1 (P1 green, medium-persistence), 1EP2 (P2 yellow-green, long-persistence), 1EP11 (P11 blue, short-persistence) – 1" (2.5 cm) CRT used in oscilloscopes, electrostatic deflection
  • 2AP1, 2BP1 – 2" (5.1 cm) CRT used in oscilloscopes, electrostatic deflection
  • 3ABP1, 3ABP2, 3ABP7 (blue/yellow, short/long), 3ABP11 – Dual-beam 3" (7.6 cm) CRT used in oscilloscopes, electrostatic deflections
  • 4AP10 – 4" (10 cm) Skiatron, a CRT where the conventional light-emitting Phosphor layer is replaced with a scotophor such as Potassium chloride, which has the property that when a crystal is struck by an electron beam, it would change from translucent white to a dark magenta, and when flooded with high-intensity infrared, or by electro-thermal heating, would change back to translucent white.[19]: 2  It therefore needs backlighting or external illumination like today's electronic paper[20][21]
  • 4DP1, 4DP2, 4DP7, 4DP11 – Dual-beam 4" CRT used in oscilloscopes, electrostatic deflections
  • 5AZP4 – 5" Projection CRT, 40 kV anode voltage, considerable X-radiation, 50° magnetic deflection, P4 white, medium-persistence, casts an 8 ft × 6 ft (2.4 m × 1.8 m) image
  • 5BP1 (1802-P1) – 5" (13 cm) CRT used in pre-World War II oscilloscopes, electrostatic deflection, P1 green, medium-persistence[22]
  • 5BP3 (1802-P3) – Pre-World War II, 5" CRT, electrostatic deflection, P3 yellow, medium-persistence[22]
  • 5BP4 (1802-P4) – 5" CRT used in pre-World War II television receivers, such as the RCA TRK-5 and in early radars such as the SCR-268 and SCR-270,[23] electrostatic deflection, P4 white, medium-persistence[22]
  • 5BP11A – 5" CRT, electrostatic deflection, P11 blue, short-persistence[24]
  • 5CEP11 (blue, short); 10VP15, 5AKP15, 5DKP15, 5ZP15 (blue-green, extremely short); 5BNP16, 5CEP16, 5DKP16, 5ZP16 (violet/near-ultraviolet, very short); 5AKP24, 5AUP24, 5DKP24, 5ZP24 (green, short) – CRT-type flying-spot scanners used in telecines
  • 5TP4 – 5" Projection CRT, 27 kV anode voltage, considerable X-radiation, 50° magnetic deflection, P4 white, medium-persistence
  • 6DP1, 6DP2, 6DP7, 6DP11, 6DP14 (purple/orange, medium/long), 6DP19 (orange, long), 6DP25 (orange, very long) – Triple-beam 6" (15 cm) CRT used in oscilloscopes, electrostatic deflections
  • 7JP1 – 7" (18 cm) CRT used in early postwar oscilloscopes, electrostatic deflection, P1 green, medium-persistence[25]
  • 7JP4 – 7" CRT common in early postwar TV receivers, electrostatic deflection, P4 white, medium-persistence[25]
  • 7JP7 – 5½" (14 cm usable screen diameter) CRT used in early postwar radar displays, electrostatic deflection, P7 blue/yellow, short/long-persistence[25]
  • 7NP4 (60 ft (18 m) projection distance), 7WP4 (80 ft (24 m) projection distance) – 7" Theatric projection CRTs, 75 kV anode voltage, considerable X-radiation, magnetic deflection, P4 white, medium-persistence, cast a 20 ft × 15 ft (6.1 m × 4.6 m) image
  • 8CP1, 8CP2, 8CP4, 8CP5 (blue, very short), 8CP7, 8CP11 – 8" (20 cm) CRT used in oscilloscopes, electrostatic deflection
  • 15HP22 – 15" (38 cm) Color CRT, 45° magnetic deflection, P22 RGB, medium-persistence
  • 25AP22 – 25" (64 cm) Color CRT, 90° magnetic deflection, P22 RGB, medium-persistence
  • 30BP4 – 30" (76 cm) CRT used in 1950s premium television receivers, 90° magnetic deflection, P4 white, medium-persistence

RMA professional tubes system

The system was used in 1942–44 for professional/industrial/computer/telecommunications vacuum and gas-filled tubes, and assigned numbers with the base form "1A21" (therefore also referred to as the "1A21 system")[18]

  • A digit: Filament/heater power rating:
  • 1 – No filament/heater; cold cathode or solid state device
  • 2 – Up to 10 W
  • 3 – 10...20 W
  • 4 – 20...50 W
  • 5 – 50...100 W
  • 6 – 100...200 W
  • 7 – 200...500 W
  • 8 – 500W...1 kW
  • 9 – More than 1 kW
  • A letter: Function/type:
    Note: Dual-system tubes (like the 3E29 or 8D21) are assigned one letter corresponding to one system
  • Two-element devices such as:
  • Nullodes (discharge tubes which have no electrodes and interact only with electromagnetic fields passing through them) such as:
  • TR (Transmit/receive) cell, a water vapor discharge tube for use with waveguides in radar systems, short-circuits the receiver input to protect it while the transmitter operates on a shared antenna
  • ATR (Anti-transmit/receive) cell, decouples the radar transmitter from the antenna while not operating, to prevent it from wasting received energy
  • PTR (Pre-transmit/receive) cell, a low-Q discharge tube, precedes the main TR cell and produces a preliminary reflection to reduce the power level at the main TR cell
  • A sequentially assigned 2-digit number, beginning at 21 to avoid possible confusion with RETMA tube or CRT Phosphor designations
  • Optionally, a possible dash followed by a RETMA suffix

For examples see below

EIA professional tubes system

Tubes and other devices

A four-digit system from 5500 to 8999 was maintained by JETEC since 1944 and by EIA since 1957, for professional/industrial/computer/telecommunications vacuum and gas-filled tubes, and all sorts of other devices requiring to be sealed off against the external atmosphere

Some manufacturers preceded the EIA number with a manufacturer's code:

Optionally, a possible dash followed by a RETMA suffix

For examples see below

Spectral response designations of photosensitive materials

These codes apply to phototubes, photomultipliers, photoresistors, photodiodes, video camera tubes, and image converters/intensifiers[26]: 21, 88 [27]

  • S1Photocathode, photosensitive material: Ag-O-Cs (Caesium-on-oxidated-Silver), envelope/window: Lime glass such as Corning 0080 (λcutoff=300 nm), k=93.9 lm⁄W, Styp=25 µA⁄lm, Smax=60 µA⁄lm, λmax=800 nm, σtyp=235 mA⁄W, QE=0.36 %, DE=900 fA⁄cm2, transmission-mode, 300...1200 nm, high dark current, used mainly in near-IR, with the photocathode cooled
  • S2 – Similar to S1, deprecated by EIA
  • S3 – Photocathode, Ag-O-Rb (Rubidium-on-oxidated-Silver), Lime, k=286 lm⁄W, Styp=6.5 µA⁄lm, Smax=20 µA⁄lm, λmax=420 nm, σtyp=1.86 mA⁄W, QE=0.55 %
  • S4 – Photocathode, Cs-Sb (Caesium-activated Antimony), Lime, k=977 lm⁄W, Styp=40 µA⁄lm, Smax=110 µA⁄lm, λmax=400 nm, σtyp=39.1 mA⁄W, QE=12 %, DE=0.2 fA⁄cm2
  • S5 – Photocathode, Cs-Sb, UV-transparent glass such as Corning 9741, k=1252 lm⁄W, Styp=40 µA⁄lm, Smax=80 µA⁄lm, λmax=340 nm, σtyp=50.1 mA⁄W, QE=18 %, DE=0.3 fA⁄cm2 [28]
  • S6 – Photocathode, Sodium, unspecified glass
  • S7 – Photocathode, Ag-O-Cs-Rb, Pyrex hard glass
  • S8 – Photocathode, Cs-Bi (Caesium-activated Bismuth), Lime, k=755 lm⁄W, Styp=3 µA⁄lm, Smax=20 µA⁄lm, λmax=365 nm, σtyp=2.26 mA⁄W, QE=0.77 %, DE=0.13 fA⁄cm2
  • S9 – Photocathode, semitransparent, Cs-Sb, Lime, k=683 lm⁄W, Styp=30 µA⁄lm, Smax=110 µA⁄lm, λmax=480 nm, σtyp=20.5 mA⁄W, QE=5.3 %
  • S10 – Photocathode, semitransparent, Ag-O-Bi-Cs, Lime, k=508 lm⁄W, Styp=40 µA⁄lm, Smax=100 µA⁄lm, λmax=450 nm, σtyp=20.3 mA⁄W, QE=5.6 %, DE=70 fA⁄cm2
  • S11 – Photocathode, semitransparent, Cs-Sb, Lime, k=804 lm⁄W, Styp=60 µA⁄lm, Smax=110 µA⁄lm, λmax=440 nm, σtyp=48.2 mA⁄W, QE=14 %, DE=3 fA⁄cm2, reflective-mode, UV to visible
  • S12Photoconductor, CdS crystal with plastic coating, Lime, 350-550 nm, λmax=500 nm
  • S13 – S11 with a fused Silica window, k=795 lm⁄W, Styp=60 µA⁄lm, Smax=80 µA⁄lm, λmax=440 nm, σtyp=47.7 mA⁄W, QE=13 %, DE=4 fA⁄cm2
  • S14Photojunction, Germanium, Lime, λmax=1.5 µm
  • S15 – Photoconductor, sintered CdS, Lime, λmax=580 nm
  • S16 – Photoconductor, CdSe, Lime, λmax=730 nm
  • S17 – Photocathode, reflecting substrate, Cs-Sb, Lime, k=664 lm⁄W, Styp=125 µA⁄lm, Smax=160 µA⁄lm, λmax=490 nm, σtyp=83 mA⁄W, QE=21 %, DE=1.2 fA⁄cm2
  • S18 – Photoconductor, Sb2S3, Lime, λmax=480 nm, used in Vidicons
  • S19 – Photocathode, Cs-Sb, fused Silica, Styp=40 µA⁄lm, Smax=70 µA⁄lm, σtyp=22 mA⁄W, QE=11 %, DE=0.3 fA⁄cm2 [29]
  • S20 – Photocathode, semitransparent, Trialkali Na-K-Cs-Sb (Sodium-Potassium-Caesium-Antimony), Lime, k=428 lm⁄W, Styp=150 µA⁄lm, Smax=250 µA⁄lm, λmax=420 nm, σtyp=64.2 mA⁄W, QE=18 %, DE=0.3 fA⁄cm2, UV to near-IR, used in broadband spectrophotometry and photon counting
  • S21 – Photocathode, semitransparent, Cs-Sb, UV-transparent glass, k=779 lm⁄W, Styp=30 µA⁄lm, Smax=60 µA⁄lm, λmax=440 nm, σtyp=23.4 mA⁄W, QE=6.6 %
  • S22tbd as of 1963
  • S23 – Photocathode, Rubidium-Tellurium, fused Silica
  • S24 – Photocathode, high-temperature/low-noise Bialkali K-Cs-Sb (Potassium-Caesium-Antimony) or Na2KSb (Sodium-Potassium-Antimony), Lime, UV to red, λmax=385 nm, used in oil well logging at up to 175 °C; very low dark current at room temperature, making it ideal for use in photon counting
  • S25 – S20 with a special cathode activation to extend the range to 930 nm

Where k = Conversion factor (lm/W); Styp = typical luminous sensitivity @2780K (µA⁄lm); Smax = max. luminous sensitivity (µA⁄lm) at wavelength λmax (nm); σtyp = typical radiant sensitivity (mA⁄W);[30] QE = typical quantum efficiency (%);[31] DE = typical photocathode dark emission @25°C (fA⁄cm2)

Eimac transmitting tubes

Pre-Eimac, developed by Bill Eitel (W6UF) and Jack McCullough (W6CHE) while still working for Heintz & Kaufman:

  • HK354 – 150 W, 15 MHz Gammatron Radiation-cooled power triode, μ=14, 5 V/10 A filament, Tantalum anode, Nonex hard glass envelope, B4F/U4J Jumbo base with anode on top cap; predecessor of the 150T (=250TL), the first Eimac tube
Before 1945

From 1934 to 1945, Eimac made only convection/radiation-cooled, directly heated rectifiers and power triodes.[32] Eimac soon found that their early anode dissipation ratings were too cautious[33]

  • 15E = 3-15A3 = 4C30 = 8023 – 20 W, 600 MHz Miniature pulse power triode, μ=25, 5 V/4 A filament, grid on top pin and anode on side pin,[34] used as power oscillator, also popular as thermally-limited (=saturated) emission noise diode[35]: 321 
  • 15R = 4B30 – 20 kV, 20 Apeak, 30 mAavg Pulse rectifier, 5 V/4 A filament, anode on top cap[36]
  • 25T = 3-25A3 = 3C34 – 25 W Power triode, μ=24, 6.3 V/3 A filament, UX4 base with anode on top pin
  • 35T = 35TL = 3-50A4 (Grid on base), 35TG = 3-50D4 (grid on side pin) – 50 W, 100 MHz Power triode, μ=39, 5 V/4 A filament, UX4 base with anode on top pin
  • 75TL = 3-75A2 (μ=12), 75TH = 3-75A3 (μ=20) – 75 W, 40 MHz Power triode, 5 V/6.25 A filament, UX4 base with grid on side pin and anode on top pin
  • 100R = 2-100A = 8020 – 40 kV, 100 mA Thermally-limited emission rectifier, 5 V/6.5 A filament, UX4 base with anode on top cap
  • 100T = 100TL = 3-100A2 (=up-rated 50T; μ=14), 100TH = 3-100A4 (μ=38) – 100 W, 40 MHz Power triode, 5 V/6.3 A filament, UX4 base with grid on side pin and anode on top pin
  • 152TL = 3-150A2 (μ=12), 152TH = 3-150A3 (μ=20) – 150 W, 40 MHz Power triode, center-tapped 10 V/6.25 A resp. 5 V/12.5 A filament, 4-pin Bayonet base with anode on top pin
  • 250R = 2-250A – 60 kV, 250 mA Thermally-limited emission rectifier, 5 V/10.5 A filament, B4F/U4J Jumbo base with anode on top cap
  • 250T = 250TL = 3-250A2 (=up-rated 150T; μ=14), 250TH = 3-250A4 (μ=37)[37] – 250 W, 40 MHz Power triode, 5 V/10.5 A filament, B4F/U4J Jumbo base with grid on side pin and anode on top cap
  • 304TL = 3-300A2 (μ=12), 304TH = 3-300A4 (μ=20) – 300 W, 40 MHz Power triode, center-tapped 10 V/12.5 A resp. 5 V/25 A filament, 4-pin Bayonet base with grid on side cap and anode on top cap
  • 450T = 450TL = 3-450A2 (=up-rated 300T; μ=18), 450TH = 3-450A4 (μ=38)[38] – 450 W, 40 MHz Power triode, 7.5 V/12 A filament, B4F/U4J Jumbo base with grid on side cap and anode on top cap
  • 750T = 750TL = 3-750A2 (=up-rated 500T) – 750 W, 40 MHz Power triode, μ=15.5, 7.5 V/21 A filament, B4F/U4J Jumbo base with grid on side cap and anode on top cap
  • 1000T = 3-1000A4 (6C21) – 1 kW, 50 MHz Power triode, μ=35, 7.5 V/17 A filament, B4F/U4J Jumbo base with grid on side cap and and anode on top cap
  • 1500T = 3-1500A3 – 1.5 kW, 40 MHz Power triode, μ=24, 7.5 V/24 A filament, B4F/U4J Jumbo base with grid on side cap and anode on top cap
  • 2000T = 3-2000A3 – 2 kW, 40 MHz Power triode, μ=23, 10 V/25 A filament, B4F/U4J Jumbo base with grid on side cap and anode on top cap

This scheme was phased out in favor of the system below in 1945, when the FCC reallocated the VHF-FM broadcast band from 42-50 MHz to 87.5-108 MHz where tetrode transmitters were better suited at the time

  • UH50 = 3-50G2 = 304B = 834 – 50 W Radiation-cooled power triode, μ=10.6, 7.5 V/3.25 A filament, UX4 base with grid and anode on top cap. The up to cherry-red anode glow was recommended as tank/antenna tuning indicator
Since 1945

Eimac and other manufacturers of high-power RF tubes use the following code:[39]

  • A digit:
—Intensity-modulated tubes: Electrode count:
  • 2 – Diode
  • 3 – Triode
  • 4 – Tetrode
  • 5 – Pentode
—Velocity-modulated tubes: Microwave cavity count:
  • Up to 2 letters:
  • P – Pulse-rated
—Intensity-modulated tubes: Construction variant or cooling method:
  • <none> – Glass/metal envelope
  • - (Dash) or R (since 1952) – Glass envelope, radiation-cooled
  • C – Ceramic/metal envelope
  • L – External anode, liquid convection cooling
  • M, VMultiphase water/vapor-cooled
  • N – External anode, natural air convection cooling
  • S – External anode, contact/conduction cooling
  • W – Water-cooled
  • X – Forced-air cooled
—Velocity-modulated tubes: Type:
  • K – (Reflex-)Klystron
  • KDKlystrode
  • M – Modulating anode for amplifying both the video and audio carriers with the same beam supply, in analog TV transmitters
  • ST – Space-charge traveling-wave tube
  • TW – Traveling-wave tube
  • A number: Maximum anode dissipation in watts; as of 1 May 1961, Klystron maximum collector dissipation is given in kilowatts for brevity
  • One or more manufacturer-proprietary letters:
—Intensity-modulated tubes: Construction variant:
  • F
—Triodes: Flexible grid and filament leads
—Tetrodes: 26.5 V heater
  • GPyrolytic graphite grids
  • H – Flexible filament leads
  • J – Mesh-type filament
  • U – Coaxial
—Velocity-modulated tubes: Frequency range:
  • LAUHF low (analog TV broadcast <600 MHz)
  • LF, LK, LQ, LRUHF high (analog TV broadcast >600 MHz)
  • LT, LXL band
  • S – 1.55 to 3.9 GHz
  • C – 3.9 to 6.2 GHz
  • CA, CHC band, coaxial output
  • CB, CG, CK, CL, CS – C band, waveguide output
  • X – 6.2 to 10.9 GHz
  • XAX band, coaxial output
  • XD, XF, XG, XK, XN, XS – X band, waveguide output
  • An optional digit:
—Intensity-modulated tubes: Gain group:
  • 1 – ≤10
  • 2 – 11...20
  • 3 – 21...30
  • 4 – 31...50
  • 5 – 51...100
  • 6 – 101...200
  • 7 – 201...500
  • 8 – 501...1000
  • Optionally a slash ("/") followed by the RMA or EIA equivalent.

Examples:

  • 1K125CA – 1.25 W, 3.7 to 4.4 GHz, waveguide output Reflex Klystron
  • 2-01C – 3 GHz, 1 kV, 1 mA, 100 mW Rocket-type disk-seal, coaxial instrumentation rectifier diode, 5 V/310-390 mA heater
  • 2-50A – 30 kV, 75 mA, 30 W Half-wave rectifier
  • 2-2000A – 75 kV, 750 mA, 1.2 kW Half-wave rectifier
  • 2X3000F – 25 kV, 3 A, 3 kW Forced-air cooled, half-wave rectifier
  • 2KDX15LA (15 kW, 470 to 600 MHz), 2KDX15LF (15 kW, 600 to 860 MHz), 2KDX40LA, 2KDX40LF (40 kW) – Forced-air cooled, electromagnet-focused Klystrodes[40][41]
  • 2KDW60LA, 2KDW60LF – 60 kW Water-cooled, electromagnet-focused Klystrode[42]
  • 3-200A3 = 592 – 200 W, 150 MHz Glass power triode with grid on side pins and anode on top cap, 10 V/5 A filament
  • 3-400Z/8163/YD1130 – 400 W, 110 MHz Glass power triode, 5 V/14.5 A filament, B5F Giant 5-pin UY base with anode on top cap
  • 3-500Z – 500 W, 110 MHz Glass power triode, 5 V/14.5 A filament, B5F Giant 5-pin UY base with anode on top cap
  • 3-1000Z/8164 – 1 kW, 110 MHz Glass power triode, 7.5 V/21.5-22.7 A filament, B5F Giant 5-pin UY base with anode on top cap
  • 3CPN10A5/7815 (10 Wavg with convection only, contact/conduction-cooled), 3CPX100A5/7815R (100 Wavg, forced-air cooled) – 2 kWpeak, 3 GHz Ceramic/metal UHF power triode, 6.0 V/900 mA heater; pulse-rated variants of 3CX100A5
  • 3CV1500A7 – 1.5 kW Water/vapor cooled variant of the 3CX1000A7
  • 3CV30000A3, 3CV30000H3 (with flexible filament leads) – 30 kW, 100 MHz Water/vapor cooled, ceramic/metal power triode, 6.3 V/152-172 A filament
  • 3CW5000s – 5 kW Power triodes, 7.5 V/51 A filament; ceramic/metal variants of 3W5000s; water-cooled variants of 3CX2500s
  • 3CW5000A1/8240 – 75 MHz, Low-μ
  • 3CW5000F1/8241 – 30 MHz, Low-μ with flexible grid and filament leads
  • 3CW5000A3/8242 – 75 MHz, Medium-μ
  • 3CW5000F3/8243 – 30 MHz, Medium-μ with flexible grid and filament leads
  • 3CW5000H3 – 75 MHz, Medium-μ with flexible filament leads
  • 3CW10000H3 – 10 kW, 90 MHz Water-cooled, ceramic/metal medium-μ power triodes, 7.5 V/75 A filament with flexible filament leads
  • 3CW20000s – 20 kW Water-cooled, ceramic/metal power triodes, 7.5 V/100 A filament
  • 3CW20000A1 – 110 MHz, Low-μ
  • 3CW20000A3 – 140 MHz, Medium-μ
  • 3CW20000A7 – 140 MHz, High-μ
  • 3CW20000H3 – 90 MHz, Medium-μ, flexible filament leads
  • 3CW20000H7 – 110 MHz, High-μ, flexible filament leads
  • 3CW25000A3 – 25 kW, 100 MHz Water-cooled, ceramic/metal medium-μ power triodes, 6.3 V/152-172 A filament
  • 3CW30000H3 (Medium-μ), 3CW30000H7 (High-μ) – 30 kW, 90 MHz Water-cooled, ceramic/metal power triodes, 6.3 V/152-172 A filament with flexible filament leads
  • 3CW40000H3 – 40 kW, 90 MHz Water-cooled, ceramic/metal medium-μ power triodes, 10 V/152-168 A filament with flexible filament leads
  • 3CX100A5/7289 (6.0 V/1 A heater), 3CX100F5/8250 (26.5 V/220 mA heater) – 100 W, 3 GHz Oil can-type forced-air cooled, ceramic/metal disk-seal, coaxial, planar, high-μ UHF power triode, 6.3 V/1 A heater, popular among radio amateurs for 23cm-band microwave amplifiers; 2C39A with different heaters
  • 3CX300A1 – 300 W Forced-air cooled, ceramic/metal, low-μ power triode, 6.3 V/2.65 A heater
  • 3CX400A7/8874 (EIA E11-81, 11-pin with ring base), 3CX400U7/8961 (Coaxial) – 400 W, 500 MHz Forced-air cooled, ceramic/metal, high-μ power triode, 6.3 V/3 A heater
  • 3CX800A7 – 800 W, 350 MHz Forced-air cooled, ceramic/metal, high-μ power triode, 13.5 V/1.5 A heater
  • 3CX1000A7/8283 – 1 kW, 220 MHz Forced-air cooled, ceramic/metal, high-μ power triode, 5 V/30.5 A filament
  • 3CX1500A7/8877 – 1.5 kW, 110 MHz Forced-air cooled, ceramic/metal high-μ power triode, 5 V/10.5 A filament
  • 3CX2500A3/8161 (75 MHz), 3CX2500F3/8251 (30 MHz, with flexible grid and filament leads), 3CX2500H3 (75 MHz, with flexible filament leads) – 2.5 kW Medium-μ triode, 7.5 V/49-53 A filament; ceramic/metal variants of 3X2500s; forced-air cooled variants of 3CW5000A3 and 3CW5000F3
  • 3CX3000A1/8238, 3CX3000F1/8239 (with flexible grid and filament leads) – 3 kW Forced-air cooled, low-μ AF power triode, 7.5 V/49-54 A filament; ceramic/metal variants of 3X3000s
  • 3CX3000A7 (110 MHz), 3CX3000F7/8162 (30 MHz, with flexible grid and filament leads) – 3 kW Forced-air cooled, ceramic/metal, Zero-Bias, high-μ power triode, 7.5 V/50.5-51.5 A filament
  • 3CX4500F3 – 4.5 kW, 75 MHz Forced-air cooled, ceramic/metal medium-μ power triode, 7 V/78 A filament with flexible leads
  • 3CX5000A7, 3CX5000H3 (with flexible filament leads) – 5 kW, 75 MHz Forced-air cooled, ceramic/metal high-μ power triode, 10 V/17.5 A filament
  • 3CX10000s – 10 kW Forced-air cooled, ceramic/metal power triode, 7.5 V/100 A filament
  • 3CX10000A1/8158 – Low-μ, AF
  • 3CX10000A3/8159 – Medium-μ, 140 MHz, for use as self-excited high-power oscillator in induction heating equipment
  • 3CX10000A7/8160 = Siemens RS2015CL – High-μ, 110 MHz
  • 3CX10000H3 – Medium-μ, with flexible filament leads
  • 3CX10000U7 – 10 kW, 260 MHz Forced-air cooled, ceramic/metal, coaxial, high-μ power triode, 15 V/3.5 A heater
  • 3CX15000A3 (Low-μ, 100 MHz), 3CX15000A7 (Medium-μ, 110 MHz), 3CX15000H3 (Low-μ, 90 MHz, with flexible filament leads) – 15 kW Forced-air cooled, ceramic/metal power triode, 6.3 V/160 A filament
  • 3CX20000A3 (Low-μ, 90 MHz), 3CX20000A7 (Medium-μ, 110 MHz), 3CX20000H3 (Low-μ, 90 MHz, with flexible filament leads) – 20 kW Forced-air cooled, ceramic/metal power triode, 10 V/160 A filament
  • 3W5000s – 5 kW, 75 MHz Water-cooled power triodes, 7.5 V/49-54 A filament; glass/metal variants of 3CW5000s
  • 3W5000A1/8240 – Low-μ
  • 3W5000A3/8242 – Medium-μ
  • 3W5000F1/8241 – Low-μ, with flexible filament leads
  • 3W5000F3/8243 – Medium-μ, with flexible filament leads
  • 3X100A5 – Factory stress-tested 2C39A
  • 3X2500A3/8161 (75 MHz), 3X2500F3/8251 (30 MHz, with flexible grid and filament leads) – 2.5 kW Forced-air cooled, low-μ power triode, 7.5 V/51 A filament; glass/metal variants of 3CX2500s
  • 3X3000A1/8238 (AF, Low-μ), 3X3000A7 (AF/RF, Medium-μ), 3X3000F1/8239 (AF, Low-μ, with flexible grid and filament leads) – 3 kW Forced-air cooled power triode, 7.5 V/51 A filament; glass/metal variants of 3CX3000s
  • 3X12500A3 – 12.5 kW, 110 MHz Forced-air cooled, glass/metal low-μ power triode, 7.5 V/192 A filament
  • 4-65A/8165 – 65 W, 150 MHz Glass beam power tetrode, 6.0 V/3.2-3.8 A filament, 5-pin Septar base with anode on top cap
  • 4-125A/6155/4D21 – 125 W, 120 MHz Glass beam power tetrode, 5 V/6.5 A filament, B5E Giant 5-pin UY base with metal shell and anode on top cap
  • 4-250A/6156/5D22 – 250 W, 110 MHz Glass beam power tetrode, 5 V/14.5 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 4-400A/8438, 4-400C/6775 – 400 W, 110 MHz Glass radial-beam power tetrode, 5 V/14.5 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 4-500A – 500 W, 110 MHz Glass radial-beam power tetrode, 10 V/10.2 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 4-1000A/8166 – 1 kW, 110 MHz Glass beam power tetrode, 7.5 V/20-22.7 A filament, B5K Supergiant 5-pin UY base with a metal shell and anode on top cap, popular in broadcast and amateur transmitters
  • 4CM300000G = 9000 – 300 kW, 50 MHz Water/vapor ("Multiphase") cooled, ceramic/metal power tetrode used in broadcast transmitters, 15 V/480 A filament
  • 4CN15A – 15 Wavg Coolerless variant of the 4CX300A/8167 for low duty or pulse service, but may be operated immersed in a liquid coolant
  • 4CPX250K/8590 – 250 Wavg, 17.5 kWpeak, 500 MHz Forced-air cooled, ceramic/metal radial-beam grid-pulsed power tetrode, 6.0 V/2.5 A heater
  • 4CS100L – 100 W, 250 MHz Contact/conduction-cooled, ceramic/metal power tetrode + control diode to monitor the emission of the quickstart 2.1 V/7.15-8.10 A filament
  • 4CS250R – 250 W, 500 MHz Ruggedized, contact/conduction-cooled, ceramic/metal power tetrode with a Beryllia heat sink coupler, quickstart 6.0 V/2.6 A filament
  • 4CV8000A – 8 kW, 150 MHz Water/vapor cooled, ceramic/metal power tetrode, 9 V/41.5 A filament
  • 4CV20000A – 20 kW, 30 MHz Water/vapor cooled, ceramic/metal power tetrode, 7.5 V/73-78 A filament
  • 4CV35000A – 35 kW, 110 MHz Water/vapor cooled, ceramic/metal power tetrode, 6.3 V/152-168 A filament
  • 4CV50000E, 4CV50000J – 50 kW, 110 MHz Water/vapor cooled, ceramic/metal power tetrode, 12 V/220 A filament
  • 4CV75000A – 75 kW, 30 MHz Water/vapor cooled, ceramic/metal power tetrode, 10 V/300 A filament
  • 4CV100000C/8351 – 100 kW, 30 MHz Water/vapor cooled, ceramic/metal power tetrode, 10 V/300 A filament
  • 4CV250000 (30 MHz, 12.0 V/640 A filament), 4CV250000A (30 MHz, 12.0 V/660 A filament), 4CV250000B (50 MHz, 12.0 V/660 A filament) – 250 kW Water/vapor cooled, ceramic/metal power tetrode
  • 4CW800B (6.0 V/4.4 A heater), 4CW800F (26.5 V/1.1 A heater) – 800 W, 800 MHz Water-cooled, ceramic/metal power tetrode
  • 4CW2000A/8244 – 2 kW, 110 MHz Ceramic/metal radial-beam power tetrode, 6.0 V/9 A heater; water-cooled variant of 4CX1000A/8168
  • 4CW10000A/8661 – 10 kW, 110 MHz Water-cooled, ceramic/metal power tetrode, 7.5 V/73-78 A filament
  • 4CW25000A – 25 kW, 110 MHz Water-cooled, ceramic/metal power tetrode, 6.3 V/160 A filament
  • 4CW50000C/8350 (30 MHz, 10 V/300 A filament), 4CW50000E (110 MHz, 12 V/220 A filament), 4CW50000J (110 MHz, 12 V/220 A filament) – 50 kW Water-cooled, ceramic/metal power tetrode
  • 4CW100000D (30 MHz, 10 V/295 A filament), 4CW100000E (110 MHz, 15.5 V/215 A filament), 4CW100000G (110 MHz, 15.0 V/170 A filament) – 100 kW Water-cooled, ceramic/metal power tetrode
  • 4CW150000E – 150 kW, 110 MHz Water-cooled, ceramic/metal power tetrode, 15.5 V/215 A filament
  • 4CW250000A, 4CW250000B, 4CW250000V – Water-cooled variants of 4CV250000A, 4CV250000B
  • 4CX125C (6.0 V/2.6-3.1 A heater), 4CX125F (26.5 V/600-700 mA heater) – 125 W, 500 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode
  • 4CX250s – 250 W, 500 MHz Forced-air cooled, ceramic/metal radial-beam power tetrodes, favored by radio amateurs as a final amplifier
  • 4CX250B/7203 = QEL2/275 – 6.0 V/2.6 A heater, B8F/JEDEC B8-236 9-pin blow-through base
  • 4CX250BC/8957 – Long-life, tighter specs variant of 4CX250B
  • 4CX250F/7204 = 4CX250FG/8621 = QEL2/275H – 26.5 V/540 mA heater
  • 4CX250K/8245 – Coaxial variant of 4CX250B for use with a cavity resonator, 6.0 V heater
  • 4CX250M/8246 – 26.5 V heater variant of 4CX250K
  • 4CX250R/7580-W – Ruggedized variant of 4CX250B, 6.0 V heater
  • 4CX300A/8167 – 300 W, 500 MHz Forced-air cooled, ceramic/metal power tetrode, 6.0 V/2.6-3.1 A heater
  • 4CX300Y/8561 – 400 W, 110 MHz Forced-air cooled, ceramic/metal power tetrode, 6.0 V/3-3.85 A heater
  • 4CX350A/8321/YL1340 (6.0 V/2.9-3.6 A heater), 4CX350F/8322/YL1341 (26.5 V/660-810 mA heater) – 350 W Forced-air cooled, ceramic/metal radial-beam AF power tetrode; ruggedized 26.5 V heater variant: 4CX350FJ/8904
  • 4CX600s – 600 W Forced-air cooled, ceramic/metal radial-beam power tetrode
  • 4CX600A – 1.3 GHz, 6.0 V/4.8 A heater
  • 4CX600B – 500 MHz, 6.0 V/4.3 A heater for use in distributed wideband amplifiers
  • 4CX600F – 500 MHz, 26.5 V/1.05 A heater for use in distributed wideband amplifiers
  • 4CX600J/8809 – 6.0 V/5.4 A heater, Larger anode cooler
  • 4CX600JA/8921 – 6.0 V/5.4 A heater, Larger anode cooler
  • 4CX1000A/8168 (110 MHz), 4CX1000K/8352 (with a solid screen ring for UHF use) – 1 kW Ceramic/metal radial-beam power tetrode, 6.0 V/9 A heater; forced-air cooled variant of 4CW2000A/8244
  • 4CX1500A (150 MHz, 5.0 V/38.5 A filament), 4CX1500B/8660 (6.0 V/9-11 A filament) – 1.5 kW Forced-air cooled, ceramic/metal radial-beam power tetrode
  • 4CX3000A/8169 – 3 kW, 150 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 9 V/41.5 A filament
  • 4CX3500A – 3.5 kW, 220 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 5.0 V/90 A filament
  • 4CX5000A/8170 = Siemens RS2014CL – 5 kW, 110 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 7.5 V/73-78 A filament; ruggedized variant: 4CX5000R/8170-W
  • 4CX5000J/8909 – 6 kW, 100 MHz Forced-air cooled, ceramic/metal, linear radial-beam power tetrode, 7.5 V/103 A filament
  • 4CX7500A – 7.5 kW, 220 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 7.0 V/103 A filament
  • 4CX10000D/8171 (7.5 V/75 A filament), 4CX10000J (7.5 V/103 A filament) – 10 kW, 110 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode; 4CX5000A/8170 with a larger cooler
  • 4CX12000A/8989 – 12 kW, 220 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 7.5 V/120 A filament
  • 4CX15000A/8281 – 15 kW, 110 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 6.3 V/160 A filament
  • 4CX15000J/8910 = 9019 = YC-130 – More linear 4CX15000A/8281 with a 7.5 V/160 A dense mesh-type filament
  • 4CX20000A/8990, 4CX20000B, 4CX20000C – 20 kW, 110 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 10 V/140 A filament
  • 4CX25000A – 25 kW, 230 MHz Forced-air cooled, ceramic/metal radial-beam power tetrode, 9.5 V/150 A filament
  • 4CX35000A, 4CX35000C/8349 (longer screen/anode insulator for Class-C screen grid or anode modulation), 4CX35000D – 35 kW, 110 MHz Forced-air cooled, ceramic/metal power tetrode, 10 V/300 A filament, used in numerous 50-kW broadcast transmitters, often in a Doherty configuration as in the Continental Electronics 317C series
  • 4CX40000G, 4CX40000GM (Different grid pattern to reduce intermodulation distortion, made for Marconi Company Ltd) – 40 kW, 220 MHz Forced-air cooled, ceramic/metal power tetrode, pyrolytic graphite grids, 15 V/170 A filament[43]
  • 4PR60A, 4PR60B/8252 – 60 Wavg, 300 kWpeak Radiation+forced-air cooled, glass, pulse-rated power tetrode used as modulator/amplifier, 26.0 V/2.1 A heater; supersedes 715C and 5D21; ruggedized variant: 4PR60C/8252-W
  • 4PR65A/8187 – 65 Wavg Radiation+forced-air cooled, glass, pulse-rated power tetrode with a Pyrovac anode, used as modulator/amplifier, 6.0 V/3.2-3.8 A filament
  • 4PR125A/8247 – 125 Wavg Radiation+forced-air cooled, glass, pulse-rated power tetrode with a Pyrovac anode, 5.0 V/6-7 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 4PR250C/8248 – 250 Wavg Radiation+forced-air cooled, glass, pulse-rated power tetrode with a Pyrovac Tantalum anode, 5.0 V/14 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 4PR400A/8188 – 400 Wavg Radiation+forced-air cooled, glass, pulse-rated power tetrode with a Pyrovac anode, 5.0 V/13.5-14.7 A filament, B5K Supergiant 5-pin UY base with anode on top cap
  • 4PR1000A/8189 – 1 kWavg Radiation+forced-air cooled, glass, pulse-rated power tetrode with a Pyrovac anode, 7.5 V/20.0-22.7 A filament, B5K Supergiant 5-pin UY base with anode on top cap
  • 4W300B/8249 – 300 W, 500 MHz Water-cooled, glass/metal power triode, 6.0 V/2.6 A heater, B8F/JEDEC B8-236 9-pin base
  • 4W20000A/8173 – 20 kW, 220 MHz Water-cooled, glass/metal power triode, 10 V/30 A heater
  • 4X150s – 150 W, 150 MHz Forced-air cooled, glass/metal beam power tetrode
  • 4X150A/7034 = QEL1/150 – 6.0 V/2.6 A heater, B8F/JEDEC B8-236 9-pin base
  • 4X150D/7035 – 26.5 V/580 mA heater, B8F/JEDEC B8-236 9-pin base
  • 4X150G/8172 – 2.5 V/6.2-7.3 A heater, coaxial
  • 4X150R/8296 – Ruggedized, 6.0 V/2.4-3.0 A heater, B8F/JEDEC B8-236 9-pin base
  • 4X150S/8297 – Ruggedized, 26.5 V/560-680 mA heater, B8F/JEDEC B8-236 9-pin base
  • 4X250B (6.0 V/2.3-2.9 A heater), 4X250F (26.5 V/500 mA heater) – 150 W, 175 MHz Forced-air cooled, glass/metal beam power tetrode, B8F/JEDEC B8-236 9-pin base
  • 4X500A – 500 W, 120 MHz Forced-air cooled, glass/metal beam power tetrode, 5.0 V/12.2-13.7 A filament
  • 4X5000A – 5 kW, 30 MHz Forced-air cooled, glass/metal beam power tetrode, 7.5 V/75 A filament
  • 5-125B/4E27A – 125 W, 75 MHz Glass power pentode, 5 V/7.5 A filament, B7D/U7G Giant 7-pin base with anode on top cap
  • 5-500A – 500 W Glass radial-beam power pentode, 10 V/10.2 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 5CX1500A, 5CX1500B – 1.5 kW, 110 MHz Forced-air cooled, ceramic/metal radial-beam power pentode, 5.0 V/40 A filament
  • 5CX3000A – 4.0 kW, 150 MHz Forced-air cooled, ceramic/metal radial-beam power pentode, 9.0 V/39.5-43.5 A filament
  • 5K50CB – 10 kW, 4.4 to 5.0 GHz Ethylene glycol-cooled, electromagnet-focused linear-beam, 5-cavity Klystron used in C-band troposcatter systems
  • 5K70SH – 30 kW, 2.45 GHz Forced-air and water-cooled, electromagnet-focused linear-beam, 5-cavity Klystron used for industrial, microwave dielectric heating
  • 5KM300SI – 100 kW, 2.1 to 2.4 GHz Forced-air and water-cooled, electromagnet-focused linear-beam, 5-cavity Klystron used in Unified S-band ground transmitters of spacecraft communications systems
  • 6K50000LQ – 10 kW, 720 to 980 MHz Forced-air and water-cooled, permanent magnet-focused linear-beam, 6-cavity Klystron
  • 7KP50SV – 3 MWpeak, 11 kWavg, 3.43 to 3.57 GHz, 7-cavity pulsed Klystron[44]: 9 

Eimac also maintained an internal prototype numbering system consisting of the letters X or Y followed by 3 or 4 digits, such as "X-2159".

Media related to Eimac vacuum tubes at Wikimedia Commons

West European systems

Mullard–Philips system

This is actually a collection of specialized and coordinated designation systems maintained by Philips until the establishment of Pro Electron in 1966;[18][45] adhering manufacturers include AEG (de), Amperex (us), CdL (1921, French Mazda brand), CIFTE (fr, Mazda-Belvu brand), EdiSwan (uk, British Mazda brand), LaRadiotechnique Compelec (fr, CoprimMiniwatt-Dario and RTC brands), Lorenz (de), MBLE(frnl) (be, Adzam and Ultron brands), Mullard (uk), Philips (nl, Miniwatt brand), RCA (us), RFT(desv) (de), Siemens (de), Telefunken (de), Tesla (cz), Toshiba (ja), Tungsram (hu), Unitra (pl, Dolam, Polam and Telam brands) and Valvo(deit) (de).

Standard tubes

This part dates back to the common valve code key (German: Röhren-Gemeinschaftsschlüssel) negotiated between Philips and Telefunken in 1933–34.[46]: 228 [47]

Pro Electron maintained only a subset of this part since 1966, with only the first letters E, P for the heater, only the second letters A, B, C, D, E, F, H, K, L, M, Y, Z for the type, and issuing only three- and four-digit numbers starting with 1, 2, 3, 5, 8, 9 for the base.[48]

Note: Marconi preceded the M-P designation with the letter M (as in MEBC3 for EBC3), Tungsram with the letter T, Ultron (MBLE)(frnl) with the letter U and VATEA (VÁkuum TEchnológiA) Rádiótechnikai és Villamossági Rt.-t. (VATEA Radio Technology and Electric Co. Ltd., Budapest, Hungary) with the letter V

  • A – 4 V AC heater for a mains transformer
  • B180 mADC series heater
  • C – 200 mA AC/DC series heater
  • D – 1.4 V DC filament for Leclanché cells, later low-voltage/low-power filament/heater:
  • 625 mV DC directly heated for NiCd battery, series-heated two-tube designs such as hearing aids. If either filament breaks, further draining of all batteries stops[49]
  • Wide range 0.9 V to 1.55 V DC directly heated for dry cells
  • 1.25 V DC directly heated for NiCd batteries
  • 1.25 V or 1.4 V AC from a separate heater winding on CRT horizontal-output transformers, in half-indirectly heated EHT rectifiers
  • E – 6.3 V parallel heater; for 3-cell lead-acid vehicle crank batteries (mobile equipment) and for AC mains or horizontal-output transformers
  • F – 12.6 V DC parallel heater for 6-cell lead-acid vehicle crank batteries
  • G – Various heaters between 2.5 and 5.0 V AC (except 4 V) from a separate heater winding on a mains or horizontal-output transformer for the anode voltage rectifier
  • H – 150 mA AC/DC series heater; was shifted here from O
—Until at least 1938: 4 V DC filament for a 2-cell lead-acid battery[3]: 2  (no known examples assigned)
  • I – 20 V heater
  • K – 2.0 V filament/heater for a single lead-acid cell, later for AC transformers
  • L – 450 mA AC/DC series heater; was shifted here from Y around 1961 after the risk of confusing with Luftwaffe tubes had subsided
  • M – 1.9 V, directly heated
  • N – 12.6 V, indirectly heated
  • O
  • 150 mA series heater, for South American markets;[50] later shifted to H
  • Then informally used for imported RETMA 0-prefix noble gas-filled cold-cathode tubes although their letter is meaningless; domestic types were shifted to Z before their mass production started
  • Lastly assigned to semiconductors, as these also had no heater
  • P – 300 mA AC/DC series heater
  • Q – 2.4 V, indirectly heated
  • R – Not assigned to avoid any confusion with the older Telefunken "R" system or with German army tubes
  • S – 1.9 V, indirectly heated
  • T – Custom heater
  • U – 100 mA AC/DC series heater
  • V – 50 mA AC/DC series heater
  • X – 600 mA AC/DC series heater
  • Y – 450 mA AC/DC series heater, shifted to L to avoid conflicts with the professional tubes system
  • ZCold-cathode tube; was shifted here from O after the advent of semiconductors
  • Up to three letters: Function/type(s):
—Heated tubes (all heater/filament letters except O and Z):
—Heater/filament letter O (very early semiconductors):[51]
  • A – Diode
  • C – Transistor
For examples see below under O. This part lived on in the later Pro Electron semiconductor designation system (also the tube letters F "pentode" becoming "RF transistor", and L "power pentode" becoming "RF power transistor")
—Heater/filament letter Z (cold-cathode tubes):[52]
  • AArc discharge tube
  • B – Binary counter or switching tube (no known examples assigned)
  • C – Common cathode Counter Dekatron that makes only carry/borrow cathodes separately available for cascading
  • EElectrometer tube
  • G – Gating tube (no known examples assigned)
  • M – Optical indicator
  • S – Separate cathodes Counter/Selector Dekatron that makes all cathodes available on individual pins for displaying, divide-by-n counter/timer/prescalers, etc.
  • TRelay triode, a low-power triode thyratron, one starter electrode, may need illumination for proper operation if not radioactively primed
  • U – Low-power tetrode thyratron, may mean:
  • Trigger tetrode, one starter electrode and a primer (keep-alive) electrode for ion availability to keep the ignition voltage constant, for analog RC timers, voltage triggers, etc.
  • Relay tetrode, two starter electrodes to make counters bidirectional or resettable
  • WTrigger pentode, two starter electrodes and a primer electrode
  • X – Shielded Trigger pentode, two starter electrodes, a primer electrode and a conductive coating of the glass envelope inside connected to a separate pin
For examples see below under Z
  • Up to four digits: Model number
—Heater/filament letters M, N, O, Q, and S: Sequentially assigned number
—All other heater/filament letters: Base type, sequentially assigned within the number ranges listed below:
Signal tubes since 1963:
  • Even number: Low/medium/high-μ = sharp-cutoff tube
  • Odd number: Vari-μ = remote-cutoff tube
—Power pentodes and triode+power pentode combinations:
  • Even number: Linear tube for use in distortion-critical circuits such as Class-A, AB or B, SSB or audio power amplifiers
  • Odd number: Less linear tube for use in more distortion-tolerant circuits such as video or Class-C RF amplifiers
  • 1–9 – Sequentially assigned, comprising most base types popular in 1934–37:
  • P8A Side-contact 8 (near-exclusive since 1937)
  • A G or GT suffix indicates an export version with a K8A Octal base for the Australian market (EBF2G/GT, ECH3G, ECH4G, EK2G/GT, EL3G, KF3G, KK2G, KL4G)
  • V5A Side-contact 5 (AB2, CB1, CB2, EB1, EB2, KB2, UY2, VY2)
  • A4A European 4-pin (AX1)
  • O5A European 5-pin (AB1, AF2, AN1, BB1, BL2, KL1)
  • C7H European 7-pin (ACH1, AK1, BCH1, DCH1, KF1, KF2)
  • K8A Octal mostly for South American markets (OBC1, OBC3, OBF2, OCH4, OH4, OF1, OF5, OF9, OM5, PBC3, PBF2, PF9, PH4, PM5, UBC1, UBF2, UBL1, UCH4, UF8, UF9, UL1, UM4, UY1)
  • Acorn tube (DxC, D(1)xF, E1C, E(1)xF)
  • B4B Midget 4-pin Hivac subminiature hearing aid base (EY1)
  • B12A Duodecal 12-pin (E1T)
  • 10–19 – Y8A Steel tube 8-pin (introduced in 1937)
  • 20–29 – B8G 8-pin Loctal
—Before 1942:
  • K8A Octal with filament MazdaOctal-style between pins 1 and 8 (DAC21, DBC21, DCH21, DF21, DF22, DK21, DL21, DLL21, DM21)
  • P8A Side-contact 8 (FDD20)
  • 30–39 – K8A Octal with filament/heater between standard pins 2 and 7
  • 40–49 – B8A Rimlock
—Before 1947:
  • 50–59 – Miscellaneous:
  • X3A Lighthouse-type disk-seal tube with a K8A Octal base (EC56, EC57)
  • X4A etc. Rocket-type disk-seal coaxial tube (EA52, EA53, EC55)
  • B8G 8-pin Loctal (DFF50, DFF51, EF51, EF52)
  • B9G 9-pin Loctal (EC52, EC54, EE50, EF50, EF54, EF55, EF59, EFF50, EFF51)
  • K8A Octal (DAH50)
  • B9D Magnoval (E55L)
  • B26A Trochotron base (ET51)
  • A4A European 4-pin (AX50, AZ50)
  • 2+1-pin subminiature (DA50)
  • B3G 3-pin subminiature (EA50, EC53)
  • B4B Midget 4-pin Hivac subminiature hearing aid base (DC51, DD51, DF51, DL51, KC50, KC51, KD50, KE50)
  • P8A Side-contact 8 (AC50, CF50, CF51, EC50, EL50, EL51, EL53, EL54)
  • Y10A Steel tube 10-pin (UEL51)
  • B15d Noise diode base (K5xA)
  • Wire-ends (DY51, EY51, KY50, ORP5x, Z50T)
  • 60–69 – Low-frequency Pencil tubes – subminiature, all-glass, inline (Flat-Press) wire-ended tubes (DCF60, DF6x, DL6x, ORP6x)
—Before the 1950s:
  • 60 – M7A British 7-pin base (AL60)
  • 60–64 – B9G 9-pin Loctal (EFP60, EL6x, EW60)
  • 70–79 – Low-frequency Pencil tubes with circular pins or wire-ends (DC70, DF7x, DL7x, DM7x, DY70, EA7x, EC7x, ECC70, EF7x, EL71, EN70, EY70, Z7xU, Z70W)
—Before the 1950s:
  • 70–79 – B8G 8-pin Loctal (Lorenz EBL/UBL71, ECH/UCH71, EEL/UEL71, EM71, EM72, PY71, UL71)
  • O5A European 5-pin (AC101, AC104, AD101, ED100)
  • P8A Side-contact 8 (AH100)
  • B7G Miniature 7-pin (DA101, DFF101, DLL10x)
  • P5A, P7A German PTT bases (AC100, AC102, AD100, AD102)
  • S8B Wehrmacht base (AF100)
  • 110–119 – Various bases:
  • Y8A Steel tube 8-pin (EA111, EDD111, EF111, EF112, EL112, ES/US111)
  • B8A Rimlock (ECL113, ED111)
  • 130–139 – K8A Octal (EL/PL136, E130L)
  • 150–159 – Miscellaneous:
  • X3A Lighthouse-type disk-seal tube with a K8A Octal base (EC157, EC158)
  • Y8A Steel tube 8-pin (EL150)
  • Y10A Steel tube 10-pin (EL151, EL156, EZ150)
  • B10V 10-pin glass with one big pin (EL152, EL153, FL152)
  • 160–169 – Inline wire-ended low-frequency Pencil tubes (DF16x, DL16x, DM160)
—Before the 1950s:
  • 162 – Y8A Steel tube 8-pin (EC162)
  • 170–179 – RFT Gnome tubes:[54]
  • G8G 8-pin variants derived from B8G Loctal never got past prototyping, allegedly because the evacuation tip inside the narrow spigot broke off too easily
  • B11G 11-pin all-glass variant with one offset pin (EAA/UAA171, EBF/UBF171, ECH/UCH171, EEL/UEL171, EF/UF17x, EL/UL17x, EM/UM171)
  • 180–189 – B9A Noval (ECC/PCC/XCC/YCC18x, E18xCC, EF/LF/XF/YF18x, E18xF, EL18x, EY189)
  • 190–199 – B7G Miniature 7-pin (DAF191, DF/EF19x, DK192, DL19x)
  • 200–209 – B10B Decal (ECF/LCF/PCF20x, ECH/PCH200, ECL/PCL200, EFL/LFL/PFL200)
  • 230–239 – K8A Octal (ECC230, E23xL)
  • 270–279 – B11G RFT 11-pin all glass Gnome tube with one offset pin
  • 280–289 – B9A Noval (E28xCC, E28xF)
  • 300–399 – K8A Octal (EC36x, EL/PL3xx, Z30xC, Z300T)
  • 400–499 – Various bases:
  • B8A Rimlock (EF410)
  • B8G 8-pin Loctal (EL401)
  • 500–529 – B9D Magnoval (ED/PD5xx, EL/LL/PL/XL5xx, EY/GY/PY5xx, PCL501)
  • 560–599 – Miscellaneous:
  • Dekatron bases (Z5xxC, Z5xxS)
  • Nixie bases (Z5xx(0)M)
  • Noise diode bases (GA/KA56x)
  • Lighthouse-type disk-seal tube (EC560)
  • Oil can-type disk-seal tube (EC562)
  • 600–699 – Inline wire-ended low-frequency Pencil tubes (DF6xx, DL6xx, Z66xW)
  • 700–799 – Circular wire-ended low-frequency Pencil tubes (DC76x, DF703, EC760, EF7xx, Z70xU, Z700W)
  • 800–899 – B9A Noval (EAF801, EC860, ECC8xx, PCE800, ECF/LCF/PCF/XCF8xx, ECL/PCL8xx, ECLL800, EF/IF8xx, E810F, EH860, AL/EL/IL/PL8xx, EM8x0, EMM80x, DY/EY/GY/PY80x, Z86xA, Z80xU, Z8xxW, Z86xX)
  • 900–999 – B7G Miniature 7-pin (DAF961, DD960, DF9xx, DK962, DL9xx, DY900, EAA901, EC/LC/PC/XC90x, ECC96x, EH900, EZ900, Z960A, Z900T)
Special quality:
  • 1000s – Subminiature, all-glass, round wire-ended, or miniature, ceramic/metal, disk-seal tube (EC10x0)
  • 2000s – B10B Decal (ECC2000)
  • 3000s – K8A Octal (EL3010) or P8A Side-contact 8 (EY3000)
  • 5000s – B9D Magnoval (EF5000, EL50x0)
  • 8000s – B9A Noval (EC80x0, ECC8100, ECF8070, ECH8000, ED8000, EF8010, EL8000, GA8600)
  • 9000s – B7G Miniature 7-pin base

For examples see below; e.g. ECC40 is a dual triode with a 6.3 V heater and a Rimlock base; PABC80/9AK8 is a single diode + dual diode + triode with a 300 mA heater and a Noval base, also registered under RETMA as 9AK8; UM34 is a "Magic eye" tuning indicator with a 100 mA heater and an Octal base. If two tubes share the same M-P designation apart from the first letter (e.g. ECL82/6BM8, LCL82/11BM8, PCL82/16A8, UCL82/50BM8, XCL82/8B8) they will usually be identical except for heater ratings; there are exceptions, particularly among output types (for example, HL84, LL86/10CW5, PL84/15CW5, UL84/45B5, and XL86/8CW5 are series-heater versions of the EL86/6CW5 which is an EL84/6BQ5 resp. XL84/8BQ5 modified for a lower anode voltage). M-P designations do not reveal any similarity between different type families; e.g. the triode section of an ECL82 is not related to either triode of an ECC82/12AU7, whereas the triode section of an ECL86/6GW8 does happen to be similar to those of an ECC83/12AX7.

Special quality tubes

Premium/SQ tubes (also backronymed to French: "Sécurité - Qualité") for professional/industrial/computer/telecommunications purposes featured some modifications including those listed above

SQ numbering before c. 1960: Function/type letter and base type number swapped;[55] most were modified versions of standard types (ECC82/12AU7 → E82CC/6189, ECC88/6DJ8 → E88CC/6922), but some were not pin-compatible (EF80/6BX6 → E80F/6084). A few SQ tubes did not have a standard equivalent (E55L/8233, E90CC/5920, E91H/6687). For examples see below, starting at DC

SQ numbering since c. 1960: 4-digit numbers listed above;[45] for examples see below, starting at EC

—Some manufacturers simply appended the letter S to the standard typecode (EF804 → EF804S)

Professional tubes

In use since at least 1961, this part was maintained by Pro Electron after their establishment in 1966.[48]

  • Two letters: Function/type:
  • X – High-vacuum electro-optical devices
  • A sequentially assigned 4-digit number, beginning at 1000
  • An optional letter suffix:
—Variant:
  • B – Blue channel
  • G – Green channel
  • LLuminance channel
  • R – Red channel
  • TReticule
  • X – Matched to medical X-ray image intensifiers with P11 or P20 Phosphors
Product binning:
  • D – High resolution
  • M – Blemish standard

For examples see below

Transmitting tubes

In use since 1925; the coding for vacuum devices differs between Continental (Philips, LaRadiotechnique, Valvo) and British (Mullard) manufacturers

  • A letter: Function/type:
    Note: Two equal letters indicate a dual-system tube
Mullard,[56] RFT, Tungsram: Gas-filled half-wave rectifier, except
—Modified Telefunken "R" system acronyms:[57]
  • RGQ – Half-wave Mercury-vapor rectifier (German: Röhre-Gleichrichter-Quecksilber "Tube-Rectifier-Mercury")
  • RGQZ – Full-wave Mercury-vapor rectifier (German: zweiweg "two-way")
  • RSQ – Grid controlled half-wave Mercury-vapor rectifier (German: steuerbar "controllable")
  • T – RF Power triode for use as amplifier or oscillator
  • X – Hydrogen, Mercury-vapor or noble-gas thyratron
  • A letter: Filament or cathode type, or fill gas, or construction variant:
Continental intensity-modulated vacuum tubes:
  • A – Directly heated Tungsten filament
  • B – Directly heated thoriated Tungsten filament
  • C – Directly heated oxide-coated filament
  • E – Indirectly heated oxide-coated cathode
British intensity-modulated vacuum tubes:
  • D – Disk-seal construction
  • V – Indirectly heated oxide-coated cathode
  • X – Directly heated Tungsten filament
  • Y – Directly heated thoriated Tungsten filament
  • Z – Directly heated oxide-coated filament
Velocity-modulated microwave devices:
  • A – Signal (output power <1W) device for use as intermediate amplifier or low-noise receiver front end
  • B – Power (output power ≥1W) device for use in transmitters
  • N – External magnet required (Magnetrons)
  • P – Packaged construction (Magnetrons)
  • SReflex Klystron
  • T – Multiple resonator (Klystrons)
Gas-filled devices:
  • G – Mercury-vapor filling, directly heated oxide-coated filament
  • H – Hydrogen filling
  • RRare-gas filling
  • X – Xenon filling
  • An optional next letter: Cooling method or other significant characteristic:
  • G, T – Tunable microwave device
  • H – Helix or other integral cooler
  • L – Forced-air cooling
  • P – Pulse modulator tube
  • Q – Shield-grid (tetrode) thyratron
  • S
Microwave devices: Servomechanically tunable device
Other tubes: Silica envelope, to allow for a glowing anode
  • W – Water cooling
  • A number:
    Note: A leading 0 means a voltage below 1 kV, the following digit(s) then being the fractional part
Microwave tubes: Frequency in GHz
Rectifying tubes: DC output voltage in kV
Thyratrons: Peak inverse voltage in kV
Transmitting tubes: Maximum anode voltage in kV
  • A delimiter:
  • / (Slash) – Continental device
  • - (Dash) – British and/or microwave device
  • A number:
Rectifiers: Maximum average anode current in mA, or anode dissipation, or useful output power in W, at rated voltage
AF/modulator tubes: Maximum anode dissipation in W (or optionally in kW if >10 kW)
Continuously transmitting tubes: Maximum output power in W or kW in Class-C amplifier telegraphy
Pulse-rated transmitting tubes: Letter P followed by the maximum peak anode current in A
Thyratrons: Maximum average anode current:
  • 2 digits: in A
  • 3 or more digits: in mA
Backward-wave oscillators or Traveling-wave tubes: Output power:
  • 2nd letter: A – in mW
  • 2nd letter: B – in W
Klystrons: Output power in W
Reflex Klystrons: Output power in mW
CW Magnetrons: Output power in kW - a leading 0 means <1 kW, the following digit(s) then being the fractional part
Pulsed Magnetrons: Peak pulse output power in kW
  • An optional following letter:
  • A, B, C, I, K – Upgrade/variant
  • R – Ruggedized
—Base or connection method:
  • A – A4A 4-pin base
  • B – Cables
  • C – Ceramic
  • E – American Medium U7A 7-pin base
  • ED – E27 Edison screw lamp base
  • EG – E40 Goliath Edison screw lamp base
  • G – American Medium UX4 4-pin base
  • GA – American B5D/U5G Giant 5-pin UY base with a metal shell
  • GB – B4F/U4J Jumbo 4-pin base
  • GS – B4D Superjumbo 4-pin base
  • N – American Medium UY5 5-pin base
  • P – P8A Side-contact 8 base
—Cooling method:
  • A – Forced-air cooled
  • H – Helix-cooled
  • W – Water-cooled
—Heater voltage:
  • F – 12.6 V
  • H – 26.5 V

For examples see below

This part was phased out in the 1960s in favor of Professional tubes

  • A number:
  • 20–29 – Loctal 8-pin base
  • 30–39 – Octal 8-pin base
  • 50–69 – Miscellaneous
  • 80–89 – Noval base
  • 90–99 – Miniature 7-pin base
  • 150–159 – Device for photometry/spectrometry/pyrometry applications
  • A – S11, Cs-Sb
  • C – S1, Ag-O-Cs
  • D – S24, Bialkali K-Cs-Sb
  • DU – "D" with a Silica window for UV detection
  • S – Semiconductor, i.e. photoresistor
  • SBUSolar-blind Caesium telluride cathode, spectral response from UV-B to Vacuum UV, peak sensitivity 235 nm (UV-C), Silica window
  • T – S20, Trialkali Na-K-Cs-Sb, UV to near-IR, special cathode activation can extend range to 930 nm, then referred to as S25
  • TU – "T" with a Silica window for UV detection
  • U
  • S13, "A" with a Silica window for UV detection, or
  • Flame detector tube, a solar-blind, UV-triggerable gas-filled cold-cathode switching diode which itself emits UV when triggered (cf. Geiger-Müller tube)
  • A letter: Filling:
  • G – Gas-filled
  • V – High-vacuum
  • VP – Photomultiplier

Examples:

  • 20AV – High-vacuum, S11 phototube, B8G Loctal base
  • 20CG – Gas-filled, side-on, S1 phototube, B8G Loctal base
  • 20CV – High-vacuum, S1 phototube, B8G Loctal base
  • 57CV – High-vacuum, S1 photometric cell, European 4-pin base
  • 58CG – Gas-filled, head-on, S1 phototube, all-glass wire-ended
  • 58CV – High-vacuum, head-on, S1 phototube, all-glass wire-ended
  • 90AG – Gas-filled, side-on, S11 phototube, Miniature 7-pin base
  • 90AV – High-vacuum, side-on, S11 phototube, Miniature 7-pin base
  • 90CG – Gas-filled, side-on, S1 phototube, Miniature 7-pin base
  • 90CV – High-vacuum, side-on, S1 phototube, Miniature 7-pin base
  • 92AG – Gas-filled, side-on, S11 phototube, Miniature 7-pin base
  • 92AV – High-vacuum, side-on, S11 phototube, Miniature 7-pin base
  • 150AV – High-vacuum, S11 photometric cell
  • 150CV – High-vacuum, S1 photometric cell
  • 150TV – High-vacuum, S20 photometric cell
  • 150UV – High-vacuum, S13 photometric cell
  • 155UG – Gas-filled, cold-cathode, 200...290 nm UV sensitive flame detector tube, direct operation from 220VAC mains, Noval base with only 4 pins[58]
  • 61SV/7634, 62SVPbS infrared (300...3500 nm) photoresistor, all-glass with 2 wire-ends
  • 50AVP – 11-stage, head-on, S11 photomultiplier for scintillation counters, Duodecal base
  • 51UVP – 11-stage, head-on, S13 photomultiplier, Duodecal base
  • 52AVP = XP1180 – 10-stage, head-on, S11 photomultiplier, 13-pin base
  • 53AVP, 153AVP – 10-stage, head-on, S11 photomultiplier, Diheptal 14-pin base
  • 53UVP – 11-stage, head-on, S13 photomultiplier, Diheptal 14-pin base
  • 54AVP – 11-stage, head-on, S11 photomultiplier, Diheptal 14-pin base
  • 55AVP – 15-stage, head-on, S11 photomultiplier, Bidecal 20-pin base
  • 56AVP – 14-stage, head-on, S11 photomultiplier, Bidecal 20-pin base
  • 56DVP, 56DUVP – 12-stage, S24 photomultiplier, Bidecal 20-pin base
  • 56SBUVP – 14-stage, Cs-Te photomultiplier, Bidecal 20-pin base
  • 56TVP, 56TUVP – 12-stage S20 photomultiplier, Bidecal 20-pin base
  • 56UVP – 14-stage, head-on, S13 photomultiplier, Bidecal 20-pin base
  • 57AVP – 11-stage head-on, S11 photomultiplier, Diheptal 14-pin base
  • 58AVP = XP1040 – 14-stage head-on, S11 photomultiplier, Bidecal 20-pin base
  • 60DVP, 60DVP/H (with plano-concave glass adaptor) – 12-stage S24 photomultiplier for scintillation counters
  • 150AVP – 10-stage head-on, S11 photomultiplier, Duodecal base
  • 150CVP – 10-stage head-on, S1 photomultiplier, Duodecal base
  • 150UVP – 10-stage head-on, S13 photomultiplier, Duodecal base
  • 152AVP – 10-stage head-on, S11 photomultiplier, Duodecal base
  • 153AVP – 11-stage head-on, S11 photomultiplier, Diheptal 14-pin base

This part was phased out in the 1960s in favor of Professional tubes

  • A number: Burning voltage
  • A letter: Current range:
  • A – max. 10 mA
  • B – max. 22 mA
  • C – max. 40 mA
  • D – max. 100 mA
  • E – max. 200 mA
  • A sequentially assigned digit
  • An optional letter: Base:
  • EEdison screw lamp base
  • K – Octal base
  • P – Side-contact base

Examples:

  • 70B1 – Voltage-regulator tube, all-glass wire-ended
  • 75B1 – Voltage-regulator tube, Miniature 7-pin base
  • 75C1 – Voltage-regulator tube, Miniature 7-pin base
  • 83A1 = 7980 – Voltage-regulator tube, Miniature 7-pin base
  • 85A1 = 0E3 – Voltage-regulator tube, B8G Loctal base
  • 85A2 = 0G3 – Voltage-regulator tube, Miniature 7-pin base
  • 90C1 – Voltage-regulator tube, Miniature 7-pin base
  • 95A1 – Voltage-regulator tube, Miniature 7-pin base
  • 100E1 – Voltage-regulator tube, A4A European 4-pin base
  • 108C1 = 0B2 – Voltage-regulator tube, Miniature 7-pin base
  • 150A1 – Voltage-regulator tube, P8A side-contact 8 base
  • 150B2 = 6354 – Voltage-regulator tube, Miniature 7-pin base
  • 150B3 – Voltage-regulator tube, Miniature 7-pin base
  • 150C1 – Voltage-regulator tube, P8A side-contact 8 base
  • 150C2 = 0A2 – Voltage-regulator tube, Miniature 7-pin base
  • 150C4 – Voltage-regulator tube, Miniature 7-pin base

BVA code

Little is known about this 1920s code other than that BVA/BRVMA members such as Cossor, EdiSwan and M-OV/GEC based their early designation systems on it

  • B – Dual triode
  • D – Diode
  • H – High-μ/high-impedance signal triode
  • HL – Medium-μ/medium-impedance signal triode
  • L – Low-μ/low-impedance signal triode
  • P – Power tube
  • S – Screen-grid tube (tetrode or pentode)
  • U – Rectifier

Compagnie des Lampes (1888, "Métal") system

The first (1888) incarnation of La Compagnie des Lampes produced the TM tube since 1915 and devised one of the first French systems;[18][59] not to be confused with Compagnie des Lampes (1921, "French Mazda", see below). This system was also used by the British ETA[60]

  • A letter: Filament/heater voltage
  • A – 1 V
  • B – 2 V
  • D – 4 V
  • E – 5 V
  • F – 6 V
  • G – 7 V
  • Another letter: Filament/heater current
  • W – ≥200 mA
  • X – 150 mA
  • Y – 100...140 mA
  • Z – <100 mA

Examples:

  • AZ920 – Triode, μ = 9, 1 V/60 mA filament, A4A European 4-pin base
  • BW602, BW704 – Power triodes, 2 V filament, A4A European 4-pin base
  • BW604Métal secteur AF Power triode, μ = 6, 2-2.5 VAC/1.75 A heater, A4A European 4-pin base[61]
  • BW1010Métal secteur AF Triode, μ = 10, 2-2.5 VAC/1.75 A heater, A4A European 4-pin base[62]
  • BX604 = Philips B205 – Power triode, μ = 6, 2 V/150 mA filament, A4A European 4-pin base
  • BY1010, BY1210 (Telefunken RE062), BY1814, BY1815 (Philips B217), BY2010 (Telefunken RE102), BY2020, BY2043 – Triodes, 2 V filament, A4A European 4-pin base
  • DW601 = Philips E406 – Power triode, μ = 6, 4 V/1 A filament, A4A European 4-pin base
  • DW702 (Philips D410), DW1003 (Philips E409) – Power triodes, 4 V filament, O5A European 5-pin base
  • DW1111 = Philips E415, DW1508, DW3020, DW3559, DW4023 (Philips E438) – Triodes, 4 V filament, O5A European 5-pin base
  • DX502 = Philips B405, DX804 = Telefunken RE134 – Power triodes, 4 V filament, A4A European 4-pin base
  • DY604 – Power triode, μ = 6, 4 V/100 mA filament, A4A European 4-pin base
  • DZ813, DZ2222 – Triodes, 4 V filament, A4A European 4-pin base
  • GW402 (Philips F704) – Power triode, μ = 4, 7.2 V/1.2 A filament, A4A European 4-pin base

Cossor system

  • An optional number (may also appear at the end of the designation): Filament/heater voltage:[18]
  • 4, 40–49, 400–499, 506 – 4 V, Mostly indirect, heater
    Note: Some power tubes in the low 40s and 400s have a 40 V/200 mA indirect heater for use in a series heater string
  • 13 – 13 V/200 mA Indirect heater for use in vehicle equipment or in a series heater string
  • 200–299 – 2 V Filament/heater
  • 600–699 – 6 V Indirect heater
  • 825 – 7.5 V/2 A Direct heater
  • An optional prefix:
  • D – 16 V/250 mADC, indirectly heated ("DC mains operated") receiver tube for use in a series heater string running on a then-still commonplace municipal DC mains system; cf. 180mADC standard
  • M – 4-volts AC, indirectly heated ("Mains Operated") receiver tube fed in parallel from a mains transformer
  • V – Vari-μ = remote-cutoff tube
  • X – Upgraded power rating
  • Letter(s): Function/type (derived from the BVA code):
  • B – Dual power triode
  • BU (Full-wave), SU (Half-wave) – High-vacuum rectifier
  • DD – Dual diode
  • DDT, DHA – Dual diode + triode
  • DETGrid-leak detector triode
  • DG – Dual-grid triode (technically a tetrode), predecessor of the pentagrid converter
  • HL – Signal triode
  • HF, RC – Higher gm
  • LF – AF triode
  • P – Power triode
  • PA – Higher gm
  • XP – Higher power rating
  • PG – Heptode pentagrid converter
  • PT, PPA – Power pentode
  • HPT – Economy version
  • SG – Sharp-cutoff tetrode ("screened grid")
  • VS – Remote-cutoff tetrode
  • SPT, SPA (Upgraded) – Sharp-cutoff RF pentode
  • VPT, VPA (Upgraded) – Remote-cutoff RF pentode
  • STH – Triode/hexode oscillator/mixer
  • An optional suffix:
  • A – Upgraded version
  • G – Long grid base tetrode
  • /HA – High amplification
  • /LA – Low amplification
  • /PEN – Pentode (P or SG with added grids; P/PEN = PT, S/PEN = SPT, VS/PEN = VPT)
  • An optional number if none preceded the letters: Filament/heater voltage

Examples:[63]

  • 4XP – Power triode, 4 V/1 A filament, European 4-pin base
  • 41MDG – Dual-grid triode, 4 V/1 A heater, O5A European 5-pin base
  • 41MP – Power triode, 4 V/1 A heater, O5A European 5-pin base
  • 41MPG = Brimar 15A2 = Ferranti VHT4 = M-OV/GEC MX40 – Remote-cutoff heptode pentagrid converter, 4 V/1 A heater, M7A British 7-pin base
  • 41MXP = Brimar PA1 = EdiSwan AC/P1 = Mullard O54V – Power triode, 4 V/1 A heater, O5A European 5-pin base
  • 41STH = Brimar 20A1 = EdiSwan AC/TH1 = M-OV/GEC X41 = Mullard TH4A – Triode/hexode oscillator/mixer, 4 V/1.15 A heater, M7A British 7-pin base
  • 210DET – Gas-filled triode used as AM detector, 2 V/100 mA filament, European 4-pin base
  • 210HF – Triode, 2 V/100 mA filament, European 4-pin base
  • 210HL – Triode, 2 V/100 mA filament, European 4-pin base
  • 210LF – Triode, 2 V/100 mA filament, European 4-pin base
  • 210PG – Remote-cutoff heptode pentagrid converter, 2 V/100 mA filament, M7A British 7-pin base
  • 210RC – Very high-μ triode, 2 V/100 mA filament, European 4-pin base
  • 210SPT – Sharp-cutoff RF pentode, 2 V/100 mA filament, M7A British 7-pin base
  • 210VPT – Shielded remote-cutoff RF pentode, 2 V/100 mA filament, M7A British 7-pin base
  • 215P – AF Power triode, 2 V/150 mA filament, European 4-pin base
  • 220B – Dual power triode, 2 V/200 mA filament, M7A British 7-pin base (not to be confused with the Western Electric 220B single power triode)
  • 220PA – Power triode, 2 V/200 mA filament, European 4-pin base
  • 220PT – Power triode, 2 V/200 mA filament, European 4-pin base
  • 230XP – Power triode, 2 V/300 mA filament, European 4-pin base
  • 240B – Dual AF power triode, 2 V/400 mA filament, M7A British 7-pin base (not to be confused with the Amperex 240B single power triode)
  • 402P – Power triode, 40 V/200 mA heater, M7A British 7-pin base
  • 410HF – Triode, 4 V/100 mA filament, European 4-pin base
  • 610RC – Signal triode, 5.5 V/100 mA filament, European 4-pin base
  • 660SU – 1 kV, 150 mA Half-wave rectifier, 6 V/4.5 A filament, European 4-pin base
  • 825BU – 500 V, 120 mA Full-wave rectifier, 7.5 V/2 A filament, European 4-pin base
  • DD/PEN – Dual diode + remote-cutoff AF pentode used as feed-forward AGC, 4 V/1 A heater, M7A British 7-pin base
  • DDT = Brimar 11A2 = EdiSwan AC/HLDD = M-OV/GEC MHD4 = Mullard TDD4 – Dual diode + triode, 4 V/1 A heater, M7A British 7-pin base
  • DDT16 – Dual diode + high-μ triode, 16 V/250 mADC heater, M7A British 7-pin base
  • DHL – Medium-μ triode, 16 V/250 mADC heater, O5A European 5-pin base
  • DP – Power triode, 16 V/250 mADC heater, O5A European 5-pin base
  • DP/PEN – Power pentode, 16 V/250 mADC heater, M7A British 7-pin base
  • DS/PEN – Pentode, 16 V/250 mADC heater, O5A European 5-pin base
  • DVS/PEN – Remote-cutoff pentode, 16 V/250 mADC heater, O5A European 5-pin base
  • DVSG – Remote-cutoff tetrode, 16 V/250 mADC heater, O5A European 5-pin base
  • PT41 – Power pentode, 4 V/1 A filament, O5A European 5-pin base
  • SU25 – 25 kV, 1 mA EHT rectifier, 2 V/500 mA filament, Octal base
  • SU2150 (CV1120) – 8 kV, 2 mA EHT rectifier used in CRT power supplies, 2 V/1.15 A filament, European 4-pin base

EdiSwan ("British Mazda") systems

AEI-EdiSwan (British Mazda) is not to be confused with other licensees of General Electric's Mazda brand:
  • GE's own subsidiary British Thomson-Houston
  • Cie des Lampes (1921, French Mazda, see below)
  • Cie Industrielle Française des Tubes Electroniques – CIFTE (Mazda-Belvu – originating from Societé Radio Belvu; see below)[64]
  • Manufacture Belge des Lampes Électriques,(fr, nl) producing:
  • Light bulbs since 1911 under the Belgian Mazda brand
  • Electronic tubes since 1924 under the Adzam ("Mazda" spelled backwards) brand[65]
Signal and low-power tubes before c.1950

Most EdiSwan tube designations were based on the BVA code; phased out in the 1950s

Notes:

  • K8B MazdaOctal bases have a larger spigot than K8A InternationalOctal, to better protect the evacuation tip, and the filament/heater is between pins 1 and 8 (IO: 2 and 7)
  • "AC*/" types are 4-volts AC, indirectly heated ("AC mains operated") receiver tubes fed in parallel from a mains transformer
  • "DC*/" types are indirectly heated ("DC mains operated") receiver tubes for use in a series heater string running on a then-still commonplace municipal DC mains system;[66]: 113  cf. 180mADC standard

—Later additions:

Examples:

  • A40 – 600 MHz Acorn UHF triode, 4 V/250 mA heater
  • A41 – 600 MHz Acorn UHF pentode, 4 V/250 mA heater
  • AC/HL – Medium-μ AF triode, 4 V/1 A heater, O5A European 5-pin base
  • AC/HLDD = Brimar 11A2 = Cossor DDT = M-OV/GEC MHD4 = Mullard TDD4 – Dual diode + AF triode, 4 V/1 A heater, M7A British 7-pin base with control grid on top cap
  • AC/ME – "Magic Eye"-type tuning indicator, 4 V/500 mA heater; ME41 with a Shouldered envelope and a M7A British 7-pin base
  • AC/P (4 W, μ=10), AC/P1 = Brimar PA1 = Cossor 41MXP = Mullard O54V (5 W, μ=5.4) – AF power triodes, 4 V/1 A heater, O5A European 5-pin base
  • AC/P4CRT electrostatic-deflection output power triode, 4 V/1 A heater, O5A European 5-pin base with anode on top cap, binned into grades Q (μ<20), R (μ=20), S (μ>20)
  • AC/PEN = Brimar 7A2 = Cossor MP/PEN = Mullard PEN4VA – AF power pentode, 4 V/1 A heater, M7A British 7-pin base
  • AC/S2PEN = Brimar 8A1 = Cossor MS/PEN = Ferranti SPT4 = M-OV/GEC MSP4 = Mullard SP4 – RF pentode, 4 V/1 A heater, M7A British 7-pin base with anode on top cap
  • AC/SP1Dual-control RF pentode used in squelch circuits or as the reactance tube in AFC circuits, suppressor grid on a separate pin to feed a gain-control voltage to,[68] 4 V/1 A heater, M7A British 7-pin base
  • AC/SP3 – Dual-control RF pentode used in shortwave and TV receivers, 4 V/1 A heater, M7A British 7-pin base with control grid on top cap
  • AC/SP3/RH – AC/SP3 upgraded for low-hum, low-microphonics and low-noise, binned into grades A (15 dB less hum, 18 dB less microphonics) and B
  • AC/TH1 = Brimar 20A1 = Cossor 41STH = M-OV/GEC X41 = Mullard TH4ATriode/hexode oscillator/mixer, 4 V/1.3 A heater, M7A British 7-pin base with hexode control grid #1 on top cap
  • AC/TP = Mullard TP4 – 2 MHz Triode/remote-cutoff pentode oscillator/mixer, 4 V/1.25 A heater, B9H British 9-pin base with the pentode control grid on top cap
  • AC/VP1 = Brimar 9A1 = Cossor MVS/PEN = M-OV/GEC VMP4 = Mullard VP4 = Ferranti VPT4 (Anode on top cap), AC/VP2 (control grid on top cap) – RF Remote-cutoff pentode, 4 V/650 mA heater, M7A British 7-pin base
  • AC2/HL = Brimar HLA2 = Cossor 41MH = Ferranti D4 = M-OV/GEC MH41 = Mullard 904V – Medium-μ triode, 4 V/1 A heater, O5A European 5-pin base
  • AC2/PEN = Brimar 7A3 = Cossor 42MP/PEN = Ferranti PT4 = Mullard PEN4VB – AF power pentode, 4 V/1.75 A heater, M7A British 7-pin base
  • AC2/PENDD – Dual diode + AF power pentode, 4 V/2 A heater, M7A British 7-pin base with control grid on top cap
  • AC4/PEN – AF beam power pentode, 4 V/1.75 A heater, M7A British 7-pin base
  • AC5/PEN – AF beam power pentode, 4 V/1.75 A heater, M7A British 7-pin base
  • AC5/PENDD – Dual diode + AF beam power pentode, 4 V/2 A heater, M7A British 7-pin base with control grid on top cap
  • AC6/PEN – Beam power pentode used as a magnetic horizontal deflection output amplifier, 4 V/1.75 A heater, M7A British 7-pin base with anode on top cap
  • DC/HL – Medium-μ triode, 6 V/500 mADC heater, O5A European 5-pin base
  • DC/P – AF power triode, 8 V/500 mADC heater
  • DC/PEN – AF power pentode, 8 V/500 mADC heater, O5A European 5-pin base
  • DC/SG – RF tetrode, 6 V/500 mADC heater, O5A European 5-pin base
  • DC2/HLDD – Dual diode + AF triode, 25 V/100 mADC heater
  • DC2/P – AF power triode, 35 V/100 mADC heater
  • DC2/PEN – AF power pentode, 35 V/100 mADC heater, O5A European 5-pin base
  • DC2/SG – RF tetrode, 20 V/100 mADC heater
  • DC2/SGVM – Vari-μ RF tetrode, 20 V/100 mADC heater
  • DC3/HL – Medium-μ triode, 25 V/100 mADC heater, O5A European 5-pin base
  • FC141 – Heptode pentagrid converter with British grid topology, 1.4 V/50 mA filament, MazdaOctal base
  • H141D – Diode + AF triode, 1.4 V/50 mA filament, MazdaOctal base
  • HL41DD (Medium-μ), HL42DD (Vari-μ for feed-forward AGC) – Dual diode + AF triode, 4 V/650 mA heater, MazdaOctal base with control grid on top cap
  • ME41 – "Magic Eye"-type tuning indicator, 4 V/500 mA heater, MazdaOctal base, Glass Tubular envelope; Shouldered version with M7A British 7-pin base: AC/ME
  • ME91 – "Magic Eye"-type tuning indicator used in AC/DC series heater radios, 9 V/200 mA heater, MazdaOctal base, Glass Tubular envelope
  • ME920 – "Magic Eye"-type tuning indicator used in AC/DC series heater radios, 9 V/200 mA heater, M7A British 7-pin base, Shouldered envelope
  • P41 (4 V/950 mA heater), P61 (6.3 V/600 mA heater) – RF triode, μ = 17, MazdaOctal base
  • P220 (μ = 12.5), P220A (μ = 6.5) – AF Power triode used as driver for the PD220, 2 V/200 mA filament, A4A European 4-pin base
  • PD220 (gm = 900 µS), PD220A (gm = 1.6 mS) – Dual AF power triode designed for operation with positive grid bias, 2 V/200 mA filament, M7A British 7-pin base (1939); cf. Triple-Twin
  • Pen24 – 440 mW Class-A output AF power pentode, 2 V/300 mA filament, MazdaOctal base
  • Pen25 – 400 mWout AF Power pentode, 2 V/150 mA filament, MazdaOctal base
  • Pen44 – 18 W AF Beam power tetrode, 4 V/2.1 A heater, MazdaOctal base
  • Pen45 – 5.8 Wout AF Beam power tetrode, 4 V/1.75 A heater, MazdaOctal base
  • Pen45DD – Pen45 + Dual diode, 4 V/2 A heater, MazdaOctal base with control grid on top cap
  • Pen46 – 20 W Beam power tetrode used as CRT horizontal deflection amplifier, 4 V/1.75 A heater, MazdaOctal base with anode on top cap
  • Pen141 – 240 mWout AF Power pentode, 1.4 V/100 mA filament, MazdaOctal base
  • Pen220 – 290 mWout AF Power pentode, 2 V/200 mA filament, O5A European 5-pin base
  • Pen231 – 350 mWout AF Power pentode, 2 V/300 mA filament, O5A European 5-pin base
  • Pen383 – 10 W AF Beam power tetrode, 38 V/200 mA heater, MazdaOctal base
  • Pen384 – 10 W AF Beam power tetrode for use on 110V mains, 38 V/200 mA heater, MazdaOctal base
  • Pen453DD – Dual diode + 10 W AF Beam power tetrode, 45 V/200 mA heater, MazdaOctal base with control grid on top cap
  • Pen3520 – 8 W AF Power pentode, 35 V/200 mA heater, M7A British 7-pin base
  • Pen3820 – 10 W AF Beam power tetrode, 38 V/200 mA heater, M7A British 7-pin base
  • PenDD4020 – Dual diode + 10 W AF power pentode, 40 V/200 mA heater, M7A British 7-pin base
  • PenDD4021 – Dual diode + 10 W AF Beam power tetrode, 45 V/200 mA heater, M7A British 7-pin base
  • QP25Quiescent Push-Pull Dual AF power pentode, gm = 3 mS, 2 V/200 mA filament, MazdaOctal base
  • QP230QPP Dual AF power pentode, gm = 3 mS, 2 V/300 mA filament, M7A British 7-pin base
  • QP240QPP Dual AF power pentode, gm = 4 mS, 2 V/450 mA filament, B9H British 9-pin base
  • SP41 (4 V/950 mA heater), SP61 (6.3 V/600 mA heater) – Sharp-cutoff RF pentode, gm = 8.5 mS, MazdaOctal base
  • SP141 – Sharp-cutoff RF pentode, gm = 900 µS, 1.4 V/50 mA filament, MazdaOctal base
  • TH41 (4 V/1.3 A heater), TH233, TH2320, TH2321 (23 V/200 mA heater) – Triode/heptode oscillator/mixer, MazdaOctal base with heptode control grid on top cap
  • TP22, TP23, TP25, TP26 (2 V/200 mA filament), TP2620 (26 V/200 mA heater) – Triode/pentode oscillator/mixer, pentode control grid on top cap
  • U26 = 2J2/KY80CRT EHT rectifier, Noval base
  • U381 (38A3/UY85) – Half-wave rectifier, Noval base
  • UU9 (6BT4/EZ40) – Full-wave rectifier, Rimlock base
Signal and low-power tubes since c.1950

EdiSwan used both the Mullard–Philips scheme and the following system:

  • 0 – Misc. higher voltages
  • 1 – 1.4 V
  • 6 – 6.3 V
  • 10 – 100 mA
  • 20 – 200 mA
  • 30 – 300 mA
  • Letter(s): Function/type
  • CTriode/pentode, triode/hexode or triode/heptode oscillator/mixer
  • D – Signal diode(s)
  • E – Beam power tetrode
  • F – Tetrode or pentode
  • FD – Tetrode+diode(s) or pentode+diode(s)
  • FL – Tetrode+triode or pentode+triode
  • G – Rectifier
  • H – Hexode
  • K – Small gas triode or tetrode thyratron
  • L – Single or dual triode, including oscillator triode
  • LD – Triode + diode(s)
  • MOptical tuning/level indicator
  • P – Power tetrode or pentode
  • PL – Signal triode + power tetrode or pentode
  • A sequentially assigned number

Examples:

  • 1C1Pentagrid converter, 1.4 V/50 mA filament, Miniature 7-pin base
  • 1D13 – Diode, 1.4 V/150 mA heater, Miniature 7-pin base
  • 1F3 – Remote-cutoff RF pentode, 1.4 V/50 mA filament, Miniature 7-pin base
  • 1FD9 = 1S5/DAF91 – Diode + AF pentode, 1.4 V/50 mA filament, Miniature 7-pin base
  • 1P10 – Power pentode, center-tapped 2.8 V/50 mA resp. 1.4 V/100 mA filament, Miniature 7-pin base
  • 6C9 – Triode/hexode oscillator/mixer, 6.3 V/450 mA heater, Rimlock base
  • 6C10 (6CU7/ECH42) – Triode/hexode oscillator/mixer, 6.3 V/230 mA heater, Rimlock base
  • 6C31 – Triode/hexode oscillator/mixer, 6.3 V/830 mA heater, Octal base
  • 6D1 – Subminiature diode used as video detector in TV receivers, 6.3 V/150 mA heater, B3G all-glass wire-ended
  • 6D2 – Dual diode, separate cathodes, 6.3 V/300 mA heater, Miniature 7-pin base
  • 6F1 – Sharp-cutoff RF pentode, 6.3 V/350 mA heater, Rimlock base
  • 6F11 – Sharp-cutoff RF pentode, 6.3 V/200 mA heater, Rimlock base
  • 6F12 – Sharp-cutoff RF pentode, 6.3 V/300 mA heater, Miniature 7-pin base; ruggedized version: S6F12
  • 6F13 – Sharp-cutoff RF pentode, 6.3 V/350 mA heater, Rimlock base
  • 6F14 – Sharp-cutoff Video pentode, 6.3 V/350 mA heater, Rimlock base
  • 6F15 – Remote-cutoff RF pentode, 6.3 V/200 mA heater, Rimlock base
  • 6F17 – Pulse-rated RF beam power tetrode, 6.3 V/300 mA heater, Miniature 7-pin base; ruggedized versions: S6F17, S6F17F
  • 6F18 – Remote-cutoff RF pentode, 6.3 V/200 mA heater, Noval base
  • 6F21 – Remote-cutoff RF pentode, 6.3 V/200 mA heater, Miniature 7-pin base
  • 6F22 = 6BK8/6CF8/EF86 – Low-noise AF pentode, 6.3 V/200 mA heater, Noval base
  • 6F23 = 6EL7 – Sharp-cutoff Video pentode, 6.3 V/300 mA heater, Noval base
  • 6F25 – Remote-cutoff RF frame-grid pentode, 6.3 V/300 mA heater, Noval base
  • 6F26 – Remote-cutoff RF pentode, 6.3 V/300 mA heater, Noval base
  • 6F32Dual-control, semiremote-cutoff pentode used as the reactance tube in AFC circuits,[68] 6.3 V/630 mA heater, MazdaOctal base
  • 6F33 – Dual-control, semiremote-cutoff pentode, 6.3 V/350 mA heater, Miniature 7-pin base; ruggedized version: S6F33
  • 6FL2 = ECF812 – Triode + low-power beam tetrode, Noval base; 30FL2 (=PCF812) with a 6.3 V/500 mA heater
  • 6H1 – 20 MHz Hexode, 6.3 V/200 mA heater, Miniature 7-pin base
  • 6L1 – Dual triode, 6.3 V/400 mA heater, Rimlock base
  • 6L12 = 6AQ8/ECC85 – Dual triode, 6.3 V/435 mA heater, Noval base
  • 6L18 – Triode, 6.3 V/300 mA heater, Rimlock base
  • 6L19 – Dual triode, 6.3 V/400 mA heater, Rimlock base
  • 6LD20 – Dual diode + triode, 6.3 V/250 mA heater, Rimlock base
  • 6M2 = EM35 – Dual-sensitivity tuning indicator, 6.3 V/200 mA heater, Octal base
  • 6P15 = 6BQ5/EL84 – Power pentode, 6.3 V/760 mA heater, Noval base
  • 6P25 (6M6-G/EL33) – Beam power tetrode, 6.3 V/1.1 A heater, Octal base
  • 10M2 = UM35 – Dual-sensitivity, top-view, "Magic Eye"-type tuning indicator, 12.6 V/100 mA heater, Octal base
  • 10PL12 = 50BM8/UCL82 – Triode + power pentode, 50 V/100 mA heater, Noval base
  • 11A1 – 15 W, 300 V Power triode used as series-pass regulator in stabilized DC power supplies, 6.3 V/950 mA heater, Noval base
  • 11E2 – Pulse-rated beam power tetrode, 6.3 V/900 mA heater, Octal base
  • 11E3 – Pulse-rated beam power tetrode, 4 V/2.5 A heater, M7A British 7-pin base
  • 12E1 – Beam power tetrode used as series-pass regulator in stabilized DC power supplies, 6.3 V/1.6 A heater, Octal base
  • 12E12 – Pulse-rated beam power tetrode, 26 V/1.6 A heater, A4A European 4-pin base
  • 13E1 = 7972 = EEV C1158 – 90 W Beam power tetrode used in DC power supplies, center-tapped 26 V/1.3 A resp. 13 V/2.6 A heater, Septar base
  • 19G3 – Half-wave rectifier, 4 V/1.4 A heater, Octal base
  • 19G6 – Half-wave rectifier, 4 V/500 mA heater, Miniature 7-pin base
  • 30C17 = PCF87 – Triode + remote-cutoff pentode used as VHF oscillator/mixer in analog TV receivers
  • 30FL2 = PCF812 – Triode + low-power beam tetrode, Noval base; 6FL2 (=ECF812) with a different heater
  • 30PL13 = 16GK8/PCL800 – Triode + beam power tetrode
  • 30PL14 = PCL88 – Triode + power pentode

Special quality:

  • S2P20 (5A6, 100 MHz), S2P21 (200 MHz) – 5 W VHF beam power tetrode, center-tapped 5.0 V/230 mA resp. 2.5 V/460 mA filament, Noval base
  • S11E12 = 7971 – Beam power tetrode used as series-pass or shunt regulator in stabilized DC power supplies, 6.3 V/1.6 A heater, Octal base
  • S19G6F – 6 kV, 30 mA Half-wave rectifier, 4 V/500 mA heater, Miniature 7-pin base

EdiSwan used more freeform designations for rectifiers and trigatrons; examples are:

  • 19E2 – Pulse rectifier, 4 V/2 A heater, Octal base
  • 19H1 (A4A European 4-pin base), 19H4 (Octal base) – CRT EHT rectifier, 4 V/2 A filament
  • 19H5 – Damper/rectifier diode, 4 V/4 A heater, E40 Goliath Edison screw lamp base
  • 24B1, 24B9Trigatrons
  • 29C1 – 100 V, 3 mA Directly heated, thermally-limited (=saturated) emission diode used as a heating current-controlled, variable series resistor in voltage/current stabilizer circuits, 4 V/800 mAmax uncoated Tungsten filament; cf. 5845, YA1000
Power tubes
  • Letter(s): Function/type
  • EHT, ESU – Half-wave, Mercury-vapor or Xenon or high-vacuum rectifier
  • EHZ, ES, PA, PD – Radiation-cooled power triode
  • ESA – Forced-air cooled
  • ESV – Water/vapor cooled
  • ESW – Water cooled
  • ESG – Radiation-cooled power tetrode
  • ESP – Radiation-cooled power pentode
  • EST – Full-wave Mercury-vapor rectifier
  • MR – Half-wave, Mercury-vapor rectifier incl. grid-controlled
  • T – Thyratron
  • A number

Examples:

  • ES75 (μ = 5), ES75H (μ = 11) – 1 kV, 75 W AF Power triode, 10 V/4.2 A filament, B4F/U4J Jumbo base
  • ES250M – 2 kV, 250 W RF/AF Power triode, 11 V/4 A filament, Pin+blade Jumbo base
  • ES450X – 5 kV, 450 W RF Power triode, 18 V/5.15 A filament
  • ES1101 – 1.25 kV, 40 W AF Power triode, 7.5 V/1.2 A heater, UX4 base
  • ES1102 – 1.25 kV, 100 W AF Power triode, 6 V/2.7 A heater, 4-pin base
  • MR15 – Thyratron
  • MR304 – Half-wave, Mercury-vapor rectifier
  • PA20 – 15 W AF Power triode, 2 V/2 A filament, A4A European 4-pin base
  • PA40 – 40 W AF Power triode, 4 V/2 A filament, A4A European 4-pin base

EEV system

Besides the RMA, EIA and Eimac systems, EEV also used the following system:[69]

  • Letter(s):
  • A – High-vacuum rectifier
  • B – Radiation-cooled power triode
  • BKIgnitron
  • BR – Forced-air cooled power triode
  • BW – Water-cooled power triode
  • BT – Mercury-vapor or Xenon-filled triode thyratron
  • BY – Water/vapor-cooled power triode
  • CR – Forced-air cooled power tetrode
  • CW – Water-cooled power tetrode
  • CX – Hydrogen tetrode thyratron
  • AFX – Rare-gas filled triode thyratron
  • A sequentially assigned number

Examples:

  • B1109 = 3C24 – 25 W, 60 MHz Power triode
  • B1135 = 5867 = TB3/750 = CV1350 – 350 W, 100 MHz Power triode
  • B1152 – 500 W, 50 MHz Power triode, 5 V/32.5 A filament, ventilated 4-pin base
  • B1153 – 800 W, 50 MHz Power triode, 6.3 V/32.5 A filament, ventilated 4-pin base
  • QT1257Touch button tube, an illuminated capacitance touch switch - a cold-cathode DC relay tube, external (capacitive) starter activated by touching, then the cathode glow is visible. 6-pin Octal base
  • XL601, XL602, XL603, XL627, XL628, XL631 and XL632 – Cold-cathode, gas-filled, linear, blue-violet light source (glow modulator tube) diode for rotating-drum FAX receivers, etc., modulation up to 1 MHz, 2-pin Octal base

ETL computing tubes system

The British Ericsson Telephones Limited (ETL), of Beeston, Nottingham (not to be confused with the Swedish TelefonAB Ericsson), original holder of the now-generic trademark Dekatron, used the following system:

  • A letter: Filling:
  • G – Noble gas-filled
  • V – Vacuum
  • Letter(s): Function/type:
  • C – Common cathode Counter Dekatron that makes only carry/borrow cathodes separately available for cascading
  • D – Diode, voltage-regulator tube, etc.
  • PE – Trigger pentode, two starter electrodes and a keep-alive (primer) electrode for ion availability
  • R – Register (Readout) – Digital indicator
  • STrochotron or separate cathodes Counter/Selector Dekatron that makes all cathodes available on individual pins for displaying, divide-by-n counter/timer/prescalers, etc.
  • TE – Trigger tetrode, one starter electrode and a keep-alive electrode
  • TR – Trigger triode, one starter electrode only
  • A number:
Dekatrons: Stage count
Digital indicators: Display cathode count
Diodes, voltage-regulator tubes: Nominal voltage
Trigger tubes: Ignition voltage
  • An optional slash followed by a number: Accessible cathodes count
  • A letter: Base:
  • A to F – European 4-pin, K8A Octal, B12A Duodecal phenolic bases
  • G to T – All-glass tubes with B7G Miniature 7-pin, B9A Noval, B13B, B17A, B26A, B27A bases
  • W to Z – All-glass wire-ended tube
  • An optional suffix:
  • /M – Trochotron with magnetic shielding
  • R – Ruggedized (shock/vibration-resistant)
  • /S – Tested to military specs

Examples:

  • GC10/2P – Neon-filled, 1 kHz miniature decade Counter Dekatron, a gas-filled, bidirecional decade counter tube
  • GC10A – Helium-filled, decade Counter Dekatron
  • GC10B – Neon-filled, 4 kHz long-life, decade Counter Dekatron
  • GC10/4B – 4 kHz Decade Computing Counter Dekatron with carry/borrow cathodes "0" and "9" and intermediate cathodes "3" and "5" wired to separate pins
  • GC10D – 20 kHz Decade Counter Dekatron for single-pulse operation
  • GC12/4B – 4 kHz Duodecimal Counter Dekatron with carry/borrow cathodes 11 and 12 and intermediate cathodes 6 and 8 wired to separate pins
  • GCA10G – 10 kHz max. Decade Counter Dekatron with routing guides and aux anodes to directly drive Nixie tubes, B27A base without the inner pin ring
  • GD2V – 16 J, 2 kV discharge tube, all-glass studded
  • GD75P – 75 V Voltage-regulator tube, Miniature 7-pin base
  • GD90M – 90 V Voltage-regulator tube, Miniature 7-pin base
  • GD340X – 345 V/3...200 µA Corona voltage-regulator tube, all-glass wire-ended
  • GD350X, GD350Y – 350 V/3...200 µA Corona voltage-regulator tube, all-glass wire-ended
  • GD550W – 550 V, 1.5 J Discharge tube, e.g. for power relaxation oscillators, all-glass wire-ended
  • GDT120M – 9 mA Gas-filled cold-cathode DC triode, one starter and a separate glow diode acting as an optical primer, Miniature 7-pin base
  • GR2G + -  Neon-filled digital indicator tube, 18 × 18 mm characters, side-viewing
  • GR2H + -  Neon-filled digital indicator tube, 20 × 20 mm characters, top-viewing
  • GR4G ¼ ½ ¾ 1  Neon-filled digital indicator tube, 18 × 30 mm characters, side-viewing
  • GR7M + - V A Ω % ~  Neon-filled digital indicator tube, 15.5 mm character height, top-viewing
  • GR10A – Gas-filled digital indicator tube with a dekatron-type readout
  • GR10G 0 1 2 3 4 5 6 7 8 9  Neon-filled digital indicator tube, 16.86 × 30 mm characters, side-viewing
  • GR10H 0 1 2 3 4 5 6 7 8 9  Neon-filled digital indicator tube, 12 × 19 mm characters, top-viewing
  • GR10J 0 1 2 3 4 5 6 7 8 9  Neon-filled digital indicator tube, 16.86 × 30 mm characters, side-viewing
  • GR10K 0 1 2 3 4 5 6 7 8 9  Neon-filled digital indicator tube, 12 × 19 mm characters, top-viewing
  • GR10M 0 1 2 3 4 5 6 7 8 9  Neon-filled digital indicator tube, 10 × 15.5 mm characters, top-viewing
  • GR10W 0 1 2 3 4 5 6 7 8 9  Neon-filled digital indicator tube, 8.42 × 15 mm characters, side-viewing, all-glass wire-ended
  • GR12G A B C D E F G H I J K L  Neon-filled digital indicator tube, 16 × 30 mm characters, side-viewing
  • GR12H E L M N P R S T U V W X  Neon-filled digital indicator tube, 16 × 30 mm characters, side-viewing
Note: More Nixie tubes under standard - ZM and professional - ZM
  • GS10C – 4 kHz max. Decade Counter/Selector Dekatron, top-viewing, Duodecal base
  • GS10D – Hydrogen-filled, 20 kHz max. Decade Counter/Selector Dekatron, Duodecal base
  • GS10H – 4 kHz max. Decade Counter/Selector Dekatron with routing guides, B17A base
  • GS12C – 4 kHz max. Duodecimal Counter/Selector Dekatron, with solder lugs
  • GS12D – Neon-filled, 4 kHz max. duodecimal Counter/Selector Dekatron, Duodecal base with two additional wires for the guide electrodes
  • GSA10G – 10 kHz max. Decade Counter/Selector Dekatron with routing guides and aux anodes to directly drive Nixie tubes, B27A base
  • GTE120Y – 5 mA Subminiature DC trigger tetrode, one starter and one primer, all-glass wire-ended
  • GTE130T – 8 mApeak DC trigger tetrode, one starter and one primer, close tolerance, low aging, quadrant I operation only, Noval base
  • GTE175M – 3.5 mAavg, 50 mApeak DC Trigger tetrode for Dekatron coupling circuits, one starter and one primer, Miniature 7-pin base
  • GTR120W – 9 mA Subminiature DC trigger triode for computer applications, all-glass with 3 wire-ends
  • GTR75M – 75 V Voltage-regulator tube, Miniature 7-pin base
  • GTR95M/S – 95 V Voltage-regulator tube, Miniature 7-pin base
  • GTR150 – Subminiature, primed 150 V voltage-regulator tube, all-glass wire-ended
  • VS10GTrochotron, an electron beam decade counter tube
  • VS10G-M – VS10G with a magnetic shield
  • VS10H – High-current trochotron
  • VS10K – Low-voltage trochotron

Marconi-Osram systems

For pre-BVA tubes see below

Signal and low-power tubes

The British GEC-Marconi-Osram (M-OV) designation was derived from 1920s BVA code and revised in 1936[70]: 2 [71][46]: 198ff [18]

  • Optional preceding letter(s) before the 1936 update:
  • D – 16 V/250 mADC, indirectly heated ("DC mains operated") receiver tube for use in a series heater string running on a then-still commonplace municipal DC mains system; cf. 180mADC standard
  • M – 4-volts AC, indirectly heated ("Mains operated") receiver tube fed in parallel from a mains transformer
—Since 1936: Marconi tube with an M-P designation
  • V – Vari-μ = remote-cutoff tube
  • Letter(s): Function/type
—BVA derived:
  • B – Dual triode
  • D – Single or dual diode
  • H – High-μ signal triode
  • HL – Medium-μ signal triode
  • L – Low-μ signal triode
  • LP – Power triode
  • P – Power triode up to 3 W
  • PT – Power pentode
  • PX – 3...25 W Power triode
  • S – Tetrode
  • SP – Pentode
  • U – High-vacuum rectifier
—1936 update:
  • N – Beam power tetrode or power pentode; replacing PT, MPT
  • W – Remote-cutoff pentode; replacing VMP
  • KTW – Remote-cutoff beam tetrode
  • KTZ – Sharp-cutoff beam tetrode
  • In most cases, the first digit of the following number is the heater rating:
  • 2 – 2 V
  • 3 – 13 V or 300 mA
  • 4 – 4 V
  • 5 – 5 V (Rectifiers)
  • 6, 7 – 6 V
  • An optional letter: Variant

Examples:

  • B30 – Dual Class-B power triode, 13 V/300 mA heater, M7A British 7-pin base
  • B36 (13 V/300 mA heater), B65 (6.3 V/600 mA heater) – Dual AF triode, μ = 20, 300 V anode, Octal base
  • B309 = 12AT7/ECC81 – Dual high-μ triode used as amplifier/mixer in VHF circuits, μ = 55, 300 V anode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • B319 – Dual RF triode, μ = 24, 250 V anode, 7.4 V/300 mA heater, Noval base
  • B329 = 12AU7/ECC82 – Dual medium-μ triode, μ = 17, 250 V anode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • B339 = 12AX7/ECC83 – Dual high-μ AF triode, μ = 100, 250 V anode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • B719 = 6AQ8/ECC85 – Dual VHF triode used as amplifier/mixer in FM receivers, μ = 58, 300 V anode, 6.3 V/435 mA heater, Noval base
  • D41 = EdiSwan V914 – Dual diode, 4 V/300 mA heater, O5A European 5-pin base
  • D42 – Single diode, 4 V/600 mA heater, A4A European 4-pin base
  • D63 = 6H6-G – Separate-cathode dual diode, 6.3 V/300 mA heater, Octal base
  • D77 = 6AL5/EAA91/EB91 – Separate-cathode dual diode, 6.3 V/300 mA heater, Miniature 7-pin base
  • DG2 – Dual-grid triode used as mixer (technically a tetrode), 80 V anode, 2 V/200 mA filament, O5A European 5-pin base
  • DH – High-μ AF triode, 16 V/250 mADC heater, O5A European 5-pin base
  • DH30 – Dual diode + triode, 13 V/300 mA heater, M7A British 7-pin base with control grid on top cap
  • DH63 – Dual diode + AF triode, 6.3 V/300 mA heater, Octal base
  • DH77 = 6AT6/EBC90 – Common cathode dual diode + high-μ AF triode used in FM ratio detectors, triode μ = 70, 6.3 V/300 mA heater, Miniature 7-pin base
  • DH107 – Common cathode dual diode + high-μ AF triode, triode μ = 70, 19 V/100 mA heater, Miniature 7-pin base
  • DH719 = 6AK8/EABC80 – Triple diode + triode, triode μ = 70, 6.3 V/450 mA heater, Noval base
  • DHD – Dual diode + high-μ triode, 16 V/250 mADC heater, M7A British 7-pin base
  • DL – Low-μ triode, 16 V/250 mADC heater, O5A European 5-pin base
  • DN41 – Dual diode + power pentode, 4 V/2.1 A heater, M7A British 7-pin base
  • DPT – Power pentode, 16 V/250 mADC heater, available in O5A European 5-pin or M7A British 7-pin base
  • DS – RF/IF Tetrode, 16 V/250 mADC heater, O5A European 5-pin base
  • H2 = Cossor 210RC – High-μ AF triode, μ = 35, 150 V anode, 2 V/100 mA filament, A4A European 4-pin base
  • H11, H12 – Miniature high-μ AF triodes used in hearing aids, 2 V/60 mA filament; similar to KC50, KC51, Mullard DA1
  • H30 – Dual diode + high-μ AF triode, μ = 80, 250 V anode, 13 V/300 mA heater, M7A British 7-pin base with control grid on top cap
  • H42 – Dual diode + high-μ AF triode, μ = 100, 250 V anode, 4 V/600 mA heater, M7A British 7-pin base with control grid on top cap
  • H63 = 6F5 – High-μ AF triode, 6.3 V/300 mA heater, Octal base
  • H410 (4 V/100 mA filament), H610 (6.0 V/100 mA filament) – High-μ AF triode, μ = 40, 150 V anode, A4A European 4-pin base
  • HA1 (4 V/250 mA heater), HA2 (6.3 V/150 mA heater) – 600 MHz Acorn triodes
  • HD22 – Dual diode + AF triode, 2 V/200 mA filament, μ = 27, 150 V anode, O5A European 5-pin base
  • HD23 – Dual diode + triode, 2 V/150 mA filament, μ = 28, 150 V anode, O5A European 5-pin base
  • HL2 – High-μ AF triode, 2 V/100 mA filament, μ = 27, 150 V anode, A4A European 4-pin base
  • HL210 = Cossor 210HF (2 V/100 mA filament, μ = 40), HL410 = Telefunken RE034 (4 V/100 mA filament, μ = 2.5), HL610 (6.0 V/100 mA filament, μ = 30) – High-μ AF triode, 150 V anode, A4A European 4-pin base
  • KTW21 – Remote-cutoff RF/IF beam tetrode, 2 V/100 mA filament, A4A European 4-pin base with control grid on top cap; upgraded drop-in replacement for the older W21 pentode
  • KTW61, KTW62 – Remote-cutoff RF/IF beam tetrode, 6.3 V/300 mA heater, Octal base with control grid on top cap; upgraded drop-in replacement for the older W61 pentode
  • KTW61M – KTW61 with a metal particles spray-shielded envelope
  • KTW63 – Remote-cutoff RF/IF beam tetrode, 6.3 V/300 mA heater, Octal base with control grid on top cap; upgraded drop-in replacement for the older W63 pentode
  • KTW73, KTW73M (Spray-shielded) – Remote-cutoff RF/IF beam tetrode, 6.3 V/160 mA heater, Octal base with control grid on top cap
  • KTZ41 – Sharp-cutoff RF/IF beam tetrode, 4 V/1.5 A heater, M7A British 7-pin base with control grid on top cap
  • KTZ61 – Sharp-cutoff RF/IF beam tetrode, 6.3 V/300 mA heater, Octal base with control grid on top cap
  • KTZ63 – Sharp-cutoff RF/IF beam tetrode, 6.3 V/300 mA heater, Octal base with control grid on top cap; upgraded drop-in replacement for the older Z63 pentode; beam variant of 6J7-G/EF37 with suppressor plates tied to cathode, not to a separate pin
  • KTZ73, KTZ73M (Spray-shielded) – Sharp-cutoff RF/IF beam tetrode, 6.3 V/160 mA heater, Octal base with control grid on top cap
  • L2B – Low-μ AF triode, μ = 15.5, 150 V anode, 2 V/100 mA filament, A4A European 4-pin base
  • L11, L12 – Miniature AF power triodes used in hearing aids, 2 V/60 mA filament; similar to KD50, Mullard DA2, DA3
  • L21 – Low-μ AF triode, 2 V/100 mA filament, A4A European 4-pin base
  • L30 – Low-μ AF triode, μ = 12, 200 V anode, 13 V/300 mA heater, M7A British 7-pin base
  • L63 = 6J5-G – Low-μ triode, 6.3 V/300 mA heater, Octal base
  • L77 = 6C4/EC90 – Low-μ triode, μ = 17, 6.3 V/150 mA heater, Miniature 7-pin base
  • L410 = Mullard PM4X = Philips B406 (4 V/100 mA filament), L610 (6.0 V/100 mA filament) – AF Power triode, 50-150 V anode, μ = 15, A4A European 4-pin base
  • LN309 = PCL83 – Low-μ AF triode + AF power pentode, 12.6 V/300 mA heater, Noval base
  • LP2 – AF Power triode, 150 V anode, μ = 15, 2 V/200 mA filament, A4A European 4-pin base
  • LS5A – AF Power triode, 400 V anode, μ = 2.5, 4.25-5.25 V/800 mA filament, A4A European 4-pin base
  • LS6A – AF Power triode, 400 V anode, μ = 3, 6.0 V/2 A filament, A4A European 4-pin base
  • LZ319 = 9A8/PCF80 – VHF Triode/pentode oscillator/mixer, Noval base
  • MH4 = CdL DW4011 = Cossor 41MHF = LaRadiotechnique TE24 = Telefunken REN904 = Valvo A4110 = CV399 – AF Triode, μ = 40, 200 V anode, 4 V/1 A heater, O5A European 5-pin base
  • MH40 – Microphone preamplifier triode, 4 V/1 A heater, O5A European 5-pin base
  • MH41 = Cossor 41MH – AF Triode, μ = 80, 200 V anode, 4 V/1 A heater, O5A European 5-pin base
  • MHD4 = Hivac ACDDT – Dual diode + triode, μ = 40, 250 V anode, 4 V/1 A heater, M7A British 7-pin base
  • MHL4 – AF Triode, μ = 20, 200 V anode, 4 V/1 A heater, O5A European 5-pin base
  • MKT4 – 3.2 W AF Beam power tetrode, 4 V/1 A heater, available in O5A European 5-pin or M7A British 7-pin base
  • ML4 – AF Triode, μ = 12, 250 V anode, 4 V/1 A heater, O5A European 5-pin base
  • MPT4 – AF Power pentode, μ = 100, 250 V anode, 4 V/1 A heater, available in O5A European 5-pin or M7A British 7-pin base
  • MS4 (μ = 550), MS4B (μ = 1120) – Sharp-cutoff RF/IF tetrode, 4 V/1 A heater, O5A European 5-pin base with anode on top terminal
  • MSP4 (100 V screen grid), MSP41 (240 V screen grid) – RF/AF Pentode, 4 V/1 A heater, M7A British 7-pin base
  • MU12 = EdiSwan UU4 (350 V), MU14 = UU5 = Mullard IW4-500 (500 V) – Full-wave rectifier, 4 V/2.5 A heater, A4A European 4-pin base
  • MX40 = Brimar 15A2 = Cossor 41MPG = Ferranti VHT4 – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 4 V/1 A heater, M7A British 7-pin base; similar to the Mullard FC4 octode
  • N17 = 3S4/DL92 – Power pentode
  • N18 = 3Q4/DL95 – Power pentode
  • N19 = 3V4/DL94 = EdiSwan 1P11 – Power pentode
  • N30, N30GCatkin AF power pentode, 13 V/300 mA heater, M7A British 7-pin base
  • N31 – AF Power pentode, 26 V/300 mA heater, M7A British 7-pin base
  • N37 – AF Power pentode, 13 V/300 mA heater, Miniature 7-pin base
  • N40 – First commercially available beam power tetrode, 4 V/1.3 A heater, O5A European 5-pin base[72]
  • N41 = KT41 – Power pentode, 4 V/2 A heater, M7A British 7-pin base
  • N42 – Power pentode, 4 V/1 A heater, M7A British 7-pin base
  • N43 – Power pentode, 4 V/2 A heater, M7A British 7-pin base
  • N77 = 6AM5/EL91, N78 = 6BJ5 – Power pentodes, 6.3 V/200 mA heater, Miniature 7-pin base
  • N108 – Power pentode, 40 V/100 mA heater, Miniature 7-pin base
  • N309 = 15A6/PL83 – Power pentode used as CRT cathode driver, 15 V/300 mA heater, Noval base
  • N329 = 16A5/PL82 – Power pentode used as CRT vertical deflection or AF amplifier, 16.5 V/300 mA heater, Noval base
  • N339 – Horizontal deflection power pentode, 20 V/300 mA heater, Noval base
  • N709 = 6BQ5/EL84 – AF Power pentode, 6.3 V/760 mA heater, Noval base
  • N727 = 6AQ5/EL90 – Beam power pentode, 6.3 V/450 mA heater, Miniature 7-pin base
  • P2 – AF Power triode, 150 V anode, μ = 7.5, 2 V/200 mA filament, A4A European 4-pin base
  • P240 – AF Power triode, 150 V anode, μ = 4, 2 V/400 mA filament, A4A European 4-pin base
  • P410 = Philips B409 = Telefunken RE134 = Valvo L414 (4 V/100 mA filament), P415 (4 V/150 mA filament), P425 = Mullard PM254 = Philips B405 (4 V/250 mA filament) – AF Power triode, μ = 7.5, 150 V anode, A4A European 4-pin base
  • P610 (6.0 V/100 mA filament, 150 V anode), P625 (6.0 V/250 mA filament, 250 V anode), P625A (200 V anode) – AF Power triodes, A4A European 4-pin base
  • PT2 – AF Power pentode, 2 V/200 mA filament, O5A European 5-pin base
  • PT4 – AF Power pentode, μ = 40, 200 V anode, 4 V/1 A filament, O5A European 5-pin base
  • PT15 – RF Power pentode, 6.3 V/1.3 A filament, O5A European 5-pin base with anode on top cap
  • PT25H – 25 W AF Power pentode, 400 V anode, 4 V/2 A filament, O5A European 5-pin base
  • PT240 = KT24 – AF Power pentode, 2 V/200 mA filament, O5A European 5-pin base
  • PT425 (4 V/250 mA filament), PT625 (6 V/250 mA filament) – AF Power pentode, O5A European 5-pin base
  • PX4 – 12 W AF power Triode, 4 V/1 A filament, A4A European 4-pin base
  • PX25, PX25A – 25 W AF Power triode, 4 V/2 A filament, A4A European 4-pin base
  • S12 – Miniature AF tetrode used in hearing aids, 2 V/60 mA filament; similar to KE50, Mullard DAS1
  • S21 (μ = 220, 2 V/100 mA filament), S22 = Philips B262 (μ = 350, 2 V/200 mA filament) – Sharp-cutoff tetrodes, 150 V anode, A4A European 4-pin base and top terminal
  • S23, S24 – Sharp-cutoff tetrodes, 150 V anode, 2 V/100 mA filament, A4A European 4-pin base with anode on top terminal
  • S410 (4 V/100 mA filament), S610 (6.0 V/100 mA filament) – Sharp-cutoff RF tetrode, A4A European 4-pin base
  • U10 = Telefunken RGN1054 = Mullard DW2X = EdiSwan D380B = Tungsram PV495 – Full-wave rectifier, A4A European 4-pin base
  • U12 – Full-wave rectifier, A4A European 4-pin base
  • U14 – Full-wave rectifier, A4A European 4-pin base
  • U16 – CRT EHT rectifier, A4A European 4-pin base
  • U17 – Half-wave rectifier, A4A European 4-pin base
  • U18/20 – Full-wave rectifier, A4A European 4-pin base
  • U19 – Half-wave rectifier, A4A European 4-pin base
  • U31 – Half-wave rectifier, Octal base
  • U37 – CRT EHT rectifier, wire-ends
  • U41 = 1B3-GT/1G3-GT/DY30 – CRT EHT rectifier, Octal base
  • U43 – CRT EHT rectifier, wire-ends
  • U45 – CRT EHT rectifier, wire-ends
  • U50 = 5Y3-G – Full-wave rectifier, Octal base
  • U52 = 5AS4A/5U4-GB – Full-wave rectifier, Octal base
  • U54 = GZ37 – Full-wave rectifier, Octal base
  • U78 = 6X4/EZ90 – Full-wave rectifier, Miniature 7-pin base
  • U107 – Half-wave rectifier, Miniature 7-pin base
  • U309 – CRT horizontal deflection output booster/damper/efficiency diode for analog color TV receivers, Noval base
  • U319 – Half-wave rectifier, Noval base
  • U329 – CRT horizontal deflection output booster/damper/efficiency diode for analog color TV receivers, Noval base
  • U709 = 6CA4/EZ81 – Full-wave rectifier, Noval base
  • VDS – Remote-cutoff tetrode, 16 V/250 mADC heater, O5A European 5-pin base with anode on top terminal
  • VMP4G – Remote-cutoff pentode, 4 V/1 A heater, M7A British 7-pin base with anode on top cap
  • VMS4 = Philips E445 = Telefunken RENS1214 = Valvo H4125D (semiremote-cutoff), VMS4B (remote-cutoff) – RF/IF Tetrode, 4 V/1 A heater, O5A European 5-pin base with anode on top cap
  • VP21 – Remote-cutoff pentode, 2 V/100 mA filament, M7A British 7-pin base with anode on top cap
  • VS24, VS24K (smaller envelope) – Remote-cutoff RF tetrode, 2 V/150 mA filament, A4A European 4-pin base with anode on top cap
  • W17 = 1T4/DF91 = EdiSwan 1F3 – Remote-cutoff RF/IF pentode, 1.4 V/50 mA filament, Miniature 7-pin base
  • W21 – Remote-cutoff RF/IF tetrode, 2 V/100 mA filament, A4A European 4-pin base with control grid on top cap
  • W30Catkin Remote-cutoff RF/IF tetrode, 13 V/300 mA heater, M7A British 7-pin base with anode on top cap
  • W31 = Ferranti VPTS – Remote-cutoff RF/IF pentode, 13 V/300 mA heater, M7A British 7-pin base with anode on top cap
  • W42 – Remote-cutoff RF/IF pentode, 4 V/600 mA heater, M7A British 7-pin base with control grid on top cap
  • W77 = 6CQ6/EF92 = Brimar 9D6 – Remote-cutoff RF/IF pentode, 6.3 V/200 mA heater, Miniature 7-pin base
  • W107 – Remote-cutoff RF/IF pentode, 12.6 V/100 mA heater, Miniature 7-pin base
  • W727 = 6BA6/EF93 – Remote-cutoff RF pentode, 6.3 V/300 mA heater, Miniature 7-pin base
  • X18 = 1AC6/DK92 – Heptode pentagrid converter, 1.4 V/50 mA filament, Miniature 7-pin base
  • X21 – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 2 V/100 mA filament, M7A British 7-pin base
  • X22 – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 2 V/150 mA filament, 7-pin base
  • X23Triode/hexode oscillator/mixer, 2 V/300 mA filament, M7A British 7-pin base with hexode control grid #1 on top cap
  • X30, X32 (Low hum) – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 13 V/300 mA heater, M7A British 7-pin base
  • X31 – Remote-cutoff triode/hexode oscillator/mixer, 13 V/300 mA heater, M7A British 7-pin base with hexode control grid #1 on top cap
  • X41 = Brimar 20A1 = Cossor 41STH = EdiSwan AC/TH1 = Mullard TH4A – 60 MHz Triode/hexode oscillator/mixer, 4 V/1.2 A heater, M7A British 7-pin base; upgraded drop-in replacement for the older MX40 pentagrid converter
  • X41C – X41 with a ceramic base for better frequency stability in VHF Band I analog TV tuners
  • X42 – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 4 V/600 mA heater, M7A British 7-pin base
  • X61 = 6J8-G, X61M (Spray-shielded) – Triode/heptode oscillator/mixer, 6.3 V/300 mA heater, Octal base
  • X63 = 6A8-G/PH4 – Remote-cutoff heptode pentagrid converter, 6.3 V/300 mA heater, Octal base
  • X64 = 6L7-G – Mixing heptode requiring a separate oscillator, 6.3 V/300 mA heater, Octal base
  • X65 – Remote-cutoff triode/hexode oscillator/mixer, 6.3 V/300 mA heater, Octal base with hexode control grid #1 on top cap
  • X79 = 6AE8 – Remote-cutoff triode/hexode oscillator/mixer, 6.3 V/300 mA heater, Noval base
  • X109 – Remote-cutoff triode/hexode oscillator/mixer, 19 V/100 mA heater, Noval base
  • X719 = 6AJ8/ECH81 – Remote-cutoff triode/heptode oscillator/mixer, 6.3 V/300 mA heater, Noval base
  • X727 = 6BE6/EK90 – Pentagrid converter with American grid topology, 6.3 V/300 mA heater, Miniature 7-pin base
  • Y61 (Tubular), Y63 (Shouldered) = 6G5-G/6U5-G = Mullard VI103, Y64 (Shouldered, lower target voltage) – Tuneray optical tuning/level indicator, 6.3 V/300 mA heater, Octal base
  • Z21 – Sharp-cutoff RF/IF tetrode, 2 V/100 mA filament, M7A British 7-pin base with anode on top cap
  • Z77 = 6AM6/EF91 – Sharp-cutoff RF pentode, 6.3 V/300 mA heater, Miniature 7-pin base
  • Z319 = EEV E2133 (6351) – Secondary emission, sharp-cutoff wideband pentode, 6.3 V/300 mA heater, Noval base
  • Z359 (12.6 V/300 mA heater between pins 4, 5), Z759 (6.3 V/600 mA heater between pins 5, 6) – Sharp-cutoff video pentodes, 6.3 V/300 mA heater, Noval base
  • Z719 = 6BX6/EF80 – Sharp-cutoff RF pentode, 6.3 V/300 mA heater, Noval base
  • Z729 = 6BK8/6CF8/EF86 – Sharp-cutoff, low-noise AF pentode, 6.3 V/200 mA heater, Noval base
  • ZA1 (4 V heater), ZA2 (6.3 V heater) – Acorn sharp-cutoff pentodes
  • ZD17 = 1S5/DAF91 = EdiSwan 1FD9 – Diode + AF pentode, 1.4 V/50 mA filament, Miniature 7-pin base

Marconi also traded some Mullard-Philips tubes, with a preceding letter M: MAZ1, MAZ41, MCL4, MCY1, MCY2, MDAC21, MDAF40, MDAF41, MDF21, MDK21, MDK40, MDL21, MDL41, MDM21, MEB4, MEBC3, MECH3, MECH21, MECH42, MEF5, MEF6, MEF9, MEK2, MEL3, MEL41, MEM1, MEM34, MKBC1, MUBC41, MUCH42, MUF9, MUF41, MUL41, MUM4, MUY41

Professional tubes
  • Letter(s): Function/type
Note: QA (Octal base), QE, QM, QO, QR (Miniature 7-pin base) indicate Quartz crystals
—Under the EEV system:
  • AH – Mercury-vapor rectifier
  • B – Radiation-cooled power triode
  • BR – Forced-air cooled power triode
  • BW – Water-cooled power triode
  • C – Forced-air cooled dual power tetrode
  • CR – Forced-air cooled power tetrode
  • KKlystron
  • QS – Voltage-regulator tube
  • A 3- or 4-digit number

Examples:[73]

  • A537Microphone preamplifier triode, 4 V/400 mA heater, British side-contact 4 base with control grid on top cap
  • A577 – Triode used as cathode follower rectifier in vacuum tube RF voltmeters, 4 V/1 A heater, O5A European 5-pin base with control grid on top cap, use as AF amplifier not recommended
  • A1714 (CV408) – Planar UHF triode, 6.3 V/490 mA heater, Miniature 7-pin base; similar to 9002
  • A1834 = 6AS7-G/ECC230 (CV2523) – Dual power triode used as series-pass regulator in stabilized DC power supplies, 6.3 V/2.5 A heater, Octal base
  • A2087 (CV2171) – Directly heated, thermally-limited (=saturated) emission, vacuum noise diode, 4.3 V/600 mA filament, Miniature 7-pin base
  • A2134 (CV2179) – Power pentode used as series-pass regulator in stabilized DC power supplies, 6.3 V/635 mA heater, Miniature 7-pin base
  • A2293 – Power triode used as series-pass regulator in stabilized DC power supplies, 6.3 V/950 mA heater, Noval base
  • A2521 = 6CR4 (UHF, grounded-grid, CV2453), A2599 (VHF, grounded-cathode, CV5242) – 200 MHz Triodes used as cascode amplifier, Noval base
  • A3064 = Q/A2403 = 6064 – Sharp-cutoff RF pentode; premium version of Z77 = 6AM6/EF91
  • B142 – 50 MHz, 400 W RF power triode; similar to 833A
  • Q/A2401 – Small-power VHF triode; premium version of 6C4/EC90[74]
  • Q/A2402 – AF power pentode; premium version of N77, 6AM5/EL91[75]
  • Q/A2404 = Q/D77 – Dual diode with separate cathodes; premium version of D77, 6AL5/EAA91/EB91[76]
  • Q/A2405 – 160 MHz Dual beam power tetrode, B9G 9-Pin Loctal base[77]
  • Q/A2406 – Dual high-μ triode; premium version of B309 = 12AT7/ECC81[78]
  • Q/A2408 – Dual triode, Octal base; premium version of B65[79]
  • Q/MR201 – Half-wave Mercury-vapor rectifier
  • QS1200 (6354/150B2) – Voltage-regulator tube, Miniature 7-pin base
  • QS1218 – 2 kV/250 µA Corona voltage-regulator tube, Miniature 7-pin base with anode on top cap
  • Q/U37 – CRT EHT rectifier; premium version of U37
  • Q/U452 (2 V/800 mA heater), Q/U456 (6.3 V/220 mA heater) – 17.5 kV/500 µA Oscilloscope CRT EHT rectifier
Power tubes
  • ACMAir (convection/radiation) cooled modulating AF triode
  • ACPTAir cooled pentode for transmitters
  • ACSAir cooled (screen grid) tetrode
  • ACTAir cooled triode
  • BESBright-emitter (screen grid) tetrode
  • CAM – Liquid-cooled anode modulating AF triode
  • CAR – Liquid-cooled anode rectifier
  • CAT – Liquid-cooled anode RF triode
  • CCConduction cooled UHF tetrode
  • DADirectly heated, air cooled audio triode for use as modulators and in PA systems
  • DEMDull-emitter modulating AF triode
  • DESDull-emitter (screen grid) RF tetrode
  • DETDull-emitter RF triode
  • EHT – High-voltage rectifier or triode
  • GTThyratron ("Gas triode/tetrode")
  • GHT – Hydrogen thyratron
  • GU – Mercury-vapor rectifier
  • GHU – Hydrogen or Deuterium-filled arc-discharge tube
  • GXU – Xenon-filled rectifier
  • A sequentially assigned number

Examples:

  • ACM3 – 2 kW, 15 MHz Forced-air cooled power triode used as a video modulator, 6 V/17 A filament
  • ACT9 – 800 W (convection) or 1.1 kW (forced), 15 MHz Air cooled power triode, derated up to 80 MHz, 16 V/22 A filament
  • CAM2 – 5 kW Water-cooled AF power triode, 16.5-17.5 V/24 A filament
  • CAM3 – 12 kW Water-cooled AF power triode, 17 V/70 A filament
  • DA30 – AF power triode, Pa=30 W, 4 V/2 A filament, European 4-pin base; PX25 with a wider grid pitch resulting in a lower μ
  • DA41 – AF power triode, Pa=40 W, 7.5 V/3.1 A filament, UX4 base with anode on top cap
  • DA42 – AF power triode, Pa=50 W, the only indirectly heated DA series triode, 7.5 V/1.2 A heater, UX4 base with anode on top cap; upgraded DA41
  • DA60 – AF power triode, Pa=60 W, 6 V/4 A filament, 4-pin base, first of the DA series
  • DA100 – AF power triode, Pa=100 W, 6 V/2.7 A filament, 4-pin base
  • DA250 – AF power triode, Pa=250 W, 10 V/2 A filament, 4-pin base
  • EHT7
  1. Marconi: 200 W, 60 kV Rectifier,[81] or
  2. GEC: 1.2 kW, 100 kV Modulator triode[73]: 6, 13 
  • GT1 – Mercury vapor-filled, 1 kV, 300 mAavg, 500 mARMS, 1 Apeak thyratron, 4 V/1.3 A heater, O5A European 5-pin base
  • GT1AArgon-filled, 300 V, 200 mAavg, 300 mARMS, 600 mApeak variant of GT1
  • GT1C = AN1 – Argon-filled, 500 V, 300 mAavg, 500 mARMS, 1 Apeak variant extensively used in the Colossus computer
  • GU20 (8.75 kV, 4 A, superseded by GU20/21), GU21 = EnglishElectricValve AH221 = Mullard RG4-1250 (11 kV, 4.75 A) – Half-wave Mercury-vapor rectifier, E40 Goliath Edison screw lamp base
  • KT2 – 1 W Beam power tetrode, 2 V/200 mA filament, O5A European 5-pin base
  • KT21 – 1.25 W Beam power tetrode, 2 V/300 mA filament, O5A European 5-pin base
  • KT32 – 7.5 W Beam power tetrode used in AC/DC radio receivers with series heater strings, 26 V/300 mA heater, Octal base; drop-in replacement for the 25L6-G, 25W6-GT
  • KT33 (25A6-GT) – 5 W Beam power tetrode used in AC/DC radio receivers with series heater strings, 26 V/300 mA heater, Octal base
  • KT33C – KT33 with a center-tapped heater, so it can also be wired for 13 V/600 mA
  • KT36 – 10 W Beam power tetrode used in AC/DC radio receivers with series heater strings, 26 V/300 mA heater, Octal base
  • KT41 – 8.6 W Beam power tetrode, 4 V/2 A heater, M7A British 7-pin base
  • KT55 – 25 W Beam power tetrode used in AC/DC radio receivers with series heater strings, 52 V/300 mA heater, Octal base
  • KT61 (6M6-G, EL33) – 4.3 W Beam power tetrode, 6.3 V/950 mA heater, Octal base
  • KT63 – 6 W Beam power tetrode, 6.3 V/700 mA heater, Octal base; drop-in replacement for the 6F6 power pentode
  • KT66 – 7.25 W Beam power tetrode, 6.3 V/1.27 A heater, Octal base; drop-in replacement for the 6L6-GC
  • KT67 – 25 W RF beam power tetrode, 6.3 V/1.5 A heater, B9G 9-pin Loctal base
  • KT71 (50L6-GT) – 5 W Beam power tetrode used in AC/DC radio receivers with series heater strings, 48 V/160 mA heater, Octal base
  • KT77 – 30 W Beam power tetrode, 6.3 V/1.4 A heater, Octal base; drop-in replacement for the 6CA7/EL34 power pentode
  • KT81 – KT61 with a B8G Loctal base
  • KT88 = 6550A = CV5220 (EdiSwan 12E13, Brimar 7D11) – AF beam power tetrode, two tubes are capable of providing 100 W output, Class-AB1, 6.3 V/1.6 A heater, Octal base
  • QP21 – Dual AF power pentode, 2 V/400 mA filament, M7A British 7-pin base
  • TT10 (813 = QY2-100) – 100 W, 30 MHz Beam power tetrode, 10 V/5 A filament, special 7-pin base with anode on top cap
  • TT11 – 2.7 W, 100 MHz Beam power tetrode, 6.3 V/800 mA heater, Octal base with anode on top cap
  • TT12 – 2.7 W, 20 MHz Beam power tetrode, 19 V/420 mA heater, B9G 9-pin Loctal base with anode on top cap
  • TT15 – 15 W, 160 MHz Beam power tetrode, 6.3 V/1.6 A heater, B9G 9-pin Loctal base
  • TT16D = QY3-125 – 125 W, 120 MHz Beam power tetrode, 5 V/6.5 A filament, B5F Giant 5-pin UY base with anode on top cap
  • TT20 = QQE03/20 (2B52, QQV03-20) – 2×10 W, 200 MHz Dual beam power tetrode, center-tapped 12.6 V/650 mA resp. 6.3 V/1.3 A heater, Septar base with anodes on top pins
  • TT21 = 7623 (6.3 V/1.6 A heater), TT22 = 7624 (12.6 V/800 mA heater) – 37.5 W, 30 MHz Beam power tetrode, Octal base with anode on top cap; derived from KT88
  • TT24 – 10 W, 225 MHz Dual beam power tetrode, center-tapped 6.3 V/830 mA heater, Noval base
  • TT100 – 100 W, 20 MHz beam power tetrode, center-tapped 12.6 V/1.6 A resp. 6.3 V/3.2 A heater, 12-pin base with anode on top cap

Media related to Marconi vacuum tubes at Wikimedia Commons

Mullard designations before 1934

Early, directly heated Mullard tubes were mostly assigned PM ("Philips-Mullard"),[82] followed by a number containing the filament voltage; Examples:[2]

  • PM1, PM1A = Cossor 210RC – AF Triode for use in RC-coupled amplifiers, 2 V/100 mA filament, A4A European 4-pin base
  • PM1HF = Cossor 210HF – RF/IF Triode, 2 V/100 mA filament, A4A European 4-pin base
  • PM1HL = Cossor 210HL = Dario TB282 = Tungsram HR210 – RF/AF Triode, 2 V/100 mA filament, A4A European 4-pin base
  • PM1LF = Cossor 210LF = Dario TB102 – AF Triode, 2 V/100 mA filament, A4A European 4-pin base
  • PM2, PM2A – Power triode for Class-A amplifiers, 2 V/200 mA filament, A4A European 4-pin base
  • PM2B, PM2BA – Power triode for Class-B amplifiers, 2 V/200 mA filament, M7A British 7-pin base
  • PM2DX = Dario TB172 – AF Triode, 2 V/100 mA filament, A4A European 4-pin base
  • PM4 – Power triode, 4 V/100 mA filament, A4A European 4-pin base
  • PM6 – Power triode, 6 V/100 mA filament, A4A European 4-pin base
  • PM12 (Sharp-cutoff), PM12V (remote-cutoff) – Tetrode, 2 V/150 mA filament, A4A European 4-pin base
  • PM16 – Sharp-cutoff tetrode, 6 V/75 mA filament, A4A European 4-pin base
  • PM22, PM22A, PM22C – "Super Power" pentode, 2 V/300 mA filament, A4A European 4-pin or O5A European 5-pin base
  • PM24A (4 VAC/275 mA filament), PM24B (4 VAC/1 A filament), PM24C (4 VAC/1 A filament), PM24D (4 VAC/2 A filament) – Power pentode used with a small, wirewound potentiometer across the floating AC heater supply with its slider tied to signal ground, to cancel out mains hum, O5A European 5-pin base
  • PM202 – "Super Power" triode, 2 V/200 mA filament, A4A European 4-pin base
  • PM252 – "Super Power" triode, 2 V/400 mA filament, A4A European 4-pin base
  • PM254 = M-OV/GEC P425 – "Super Power" triode, 4 V/200 mA filament, A4A European 4-pin base
  • PM256 – "Super Power" triode, 6 V/250 mA filament, A4A European 4-pin base

Many later tubes were assigned acronyms with up to three letters, followed by a number containing the heater voltage. This was phased out after 1934 when Mullard adopted the Mullard–Philips scheme.

Examples:

  • 2D4 = AB1 – Dual Diode, 4 V/650 mA heater, O5A European 5-pin base with one anode on top cap
  • 2D13, 2D13A (V5A Side-contact 5 base), 2D13C (O5A European 5-pin base) – Dual Diode, 13 V/200 mA heater, one anode on top cap
  • AP4 = Philips 4676 – 430 MHz Acorn UHF Pentode, 4 Volts heater
  • AT4 = Philips 4675 – 300 MHz Acorn UHF Triode, 4 Volts heater
  • DA1 (2 V/50 mA filament), DB1 (1.5 V/70 mA filament) – Miniature AF triodes used in Deaf Aids; similar to DC51, KC50, KC51, M-OV/GEC H11, H12
  • DA2 (2 V/50 mA filament), DA3 (2 V/55 mA filament), DB3 (1.5 V/70 mA filament) – Miniature AF power triodes used in hearing aids; similar to DD51, KD50, M-OV/GEC L11, L12
  • DAS1 (2 V/60 mA filament), DBS1 (1.5 V/70 mA filament) – Miniature AF tetrodes used in hearing aids; similar to DF51, KE50, M-OV/GEC S12
  • FC4Octode Frequency Converter, 4 V/650 mA heater, M7A British 7-pin base with #4 grid on top cap; similar to the M-OV/GEC MX40 heptode[83]
  • FC13 – FC4 with a 13 V/200 mA heater and a P8A side-contact 8 base
  • FC13C – FC13 with a M7A British 7-pin base; similar to Brimar 15D1, Cossor 13PGA, Ferranti VHTA heptodes
  • GT4A (4 V/1.2 A heater), GT4C (EC50 with a 4 V/2.4 A heater) – Gas Triodes, P8A Side-contact 8 base with grid on top cap
  • HL13 (P8A Side-contact 8 base), HL13C (M7A British 7-pin base) – Triode, 13 V/200 mA heater, grid on top cap
  • HVR1 (2 V/290 mA filament), HVR2 (4 V/650 mA filament) – Half-wave, High-Voltage Rectifier, A4A European 4-pin base with anode on top cap
  • PenA4 (4 V/1.95 A heater, M7A British 7-pin base), Pen4VA (4 V/1.35 A heater, O5A European 5-pin base with screen grid on a side terminal), Pen4VB (slow-heating PenA4) – Power Pentodes
  • Pen20 – Power Pentode, 20 V/180 mA heater, B6H European 6-pin base
  • Pen26 – Power Pentode, 24 V/200 mA heater, P8A side-contact 8 base with control grid on top cap
  • Pen36C – Power Pentode, 33 V/200 mA heater, M7A British 7-pin base
  • Pen40DD – Power Pentode + dual Diode, 44 V/200 mA heater, M7A British 7-pin base with control grid on top cap
  • SP13 – (Screen grid) RF Pentode, 13 V/200 mA heater, P8A side-contact 8 base with control grid on top cap
  • T4D – Subminiature Television Diode, 4 V/200 mA heater, all-glass wire-ended
  • TDD4 = Brimar 11A2 = Cossor DDT = EdiSwan AC/HLDD = M-OV/GEC MHD4 (4 V/550 mA heater), TDD13C (13 V/200 mA heater) – Triode + dual Diode, M7A British 7-pin base with grid on top cap
  • TH4, TH4A (4 V/1 A heater), TH13C (13 V/310 mA heater), TH21C (21 V/200 mA heater), TH22C, TH30C (29 V/200 mA heater) – Triode/Hexode oscillator/mixer, M7A British 7-pin base with #1 Hexode grid on top cap
  • TP4 = EdiSwan AC/TPTriode + Pentode, 4 V/1.25 A heater, B9H British 9-pin base with the pentode control grid on top cap
  • TSE4Television Secondary Emission pentode, 4 V/1.1 A heater, M7A British 7-pin base with control grid on top cap
  • TSP4Television high-Slope Pentode, 4 V/1.3 A heater, M7A British 7-pin base with control grid on top cap
  • VP2 = EdiSwan VP215 = M-OV/GEC VP21Vari-μ Pentode, 2 V/180 mA heater, M7A British 7-pin base
  • VP13A (P8A Side-contact 8 base), VP13C (M7A British 7-pin base) – Vari-μ Pentode, 13 V/200 mA heater, control grid on top cap

Media related to Mullard vacuum tubes at Wikimedia Commons

Philips systems

Most tubes before 1925 were assigned a letter and an optional Roman numeral (examples). Transmitting tubes started with the letter Z (Dutch: zendbuis, zendlamp).

In 1923, Philips introduced their Miniwatt brand to indicate Dull-Emitter tubes.

In 1925, the Roman numerals of tubes still in production were replaced by Arabic numerals, and since then, new tubes were assigned as explained below; new transmitting tubes were assigned according to the system above.[84]

Standard tubes 1925–34

The system consisted of one letter followed by 3 or 4 digits.[85]: 15  [3][47][18] It was phased out after 1934 when Philips adopted the Mullard–Philips scheme.

  • A letter: Filament/heater current
  • A – 60...90 mA
  • B – 100...200 mA (This designation lived on as the "B" (180 mA) in the Mullard–Philips system)
  • C – 200...390 mA (This designation lived on as the "C" (200 mA) in the Mullard–Philips system)
  • D – 400...690 mA
  • E – 700...1350 mA
  • F – 1.25...2 A
  • 1 or 2 digit(s): Filament/heater voltage
  • 2 more digits: Function/type
  • second-last digit: sequentially assigned, beginning at 4
  • last digit:
  • 1Bi-grille,[86] a space charge grid tetrode (the 2nd grid is the control grid)
  • 2 – Tetrode with a screen grid (the 1st grid is the control grid)
  • 3 – Power pentode
  • 4Binode, a diode+triode or diode+tetrode
  • 5 – Remote-cutoff RF tetrode
  • 6 – Signal pentode
  • 7 – Remote-cutoff RF pentode
  • 8 – Sharp-cutoff hexode mixer
  • 9 – Remote-cutoff hexode mixer

Examples:[87]

  • A106 – AF Triode, μ = 6, 20-100 V anode, 1.0-1.3 V/60 mA filament, A4A European 4-pin (default) base
  • A109 – AF/RF Triode, μ = 9, 20-120 V anode, 1.0-1.3 V/60 mA filament, A4A European 4-pin (default) base
  • A141 – AF/RF Space charge grid tetrode, μ = 4.5, 2-20 V anode, 1.0-1.3 V/60 mA filament, A4A European 4-pin base with the space charge grid on a lateral terminal (default)
  • A241 – AF/RF Space charge grid tetrode, μ = 4.5, 2-20 V anode, 1.7-2.0 V/60 mA filament, A4A European 4-pin base with the space charge grid on a lateral terminal (default)
  • A306 – AF Triode, μ = 6, 20-100 V anode, 2.7-3.3 V/60 mA filament, A4A European 4-pin (default) base
  • A310 – AF/RF Triode, μ = 10, 20-100 V anode, 2.7-3.3 V/60 mA filament, A4A European 4-pin (default) base
  • A341 – AF/RF Space charge grid tetrode, μ = 4.5, 2-20 V anode, 2.7-3.3 V/60 mA filament, A4A European 4-pin base with the space charge grid on a lateral terminal (default)
  • A406 – AF Triode, μ = 6, 20-100 V anode, 3.4-4.0 V/60 mA filament, A4A European 4-pin (default) base
  • A409 = Mullard PM3X – AF Triode, μ = 9, 20-150 V anode, 4 V/60 mA filament, A4A European 4-pin (default) base
  • A410 – AF/RF Triode, μ = 10, 20-100 V anode, 3.4-4.0 V/60 mA filament, A4A European 4-pin (default) base
  • A415 – AF Triode, μ = 15, 50-150 V anode, 4 V/80 mA filament, A4A European 4-pin (default) base
  • A425 = Mullard PM3DX = Telefunken RE034 = Tungsram HR406 – RF Triode, μ = 25, 50-150 V anode, 4 V/60 mA filament, A4A European 4-pin (default) base
  • A430 (AF), A435 (RF) – Triode, μ = 35, 50-150 V anode on top terminal, 4 V/60 mA filament, A4A European 4-pin (default) base
  • A441 (2-20 V anode), A441N (2-100 V anode) – Space charge grid tetrode, μ = 4.5, 4 V/80 mA filament, A4A European 4-pin base with the space charge grid on a lateral terminal (default)
  • A442 = Telefunken RES094 = Tungsram S406 – Screen grid tetrode, gm = 700 µS, μ = 150, 50-150 V anode on top terminal, 4 V/60 mA filament, A4A European 4-pin base
  • B105 – AF Power triode, μ = 5, 20-120 V anode, 1.0-1.3 V/150 mA filament, A4A European 4-pin (default) base
  • B217 – Triode, μ = 17, 150 V anode, 2 V/100 mA filament, A4A European 4-pin base
  • B228 = Cossor 210RC = M/OV H210 – Triode, μ = 28, 150 V anode, 2 V/100 mA filament, A4A European 4-pin base
  • B240 = Telefunken RE402B – Dual AF power triode, 120 V anode, output power 1.3 W, 2 V/200 mA filament, C7H European 7-pin base
  • B255 = Ferranti S2 = LaRadiotechnique TB452 – Remote-cutoff, screen grid tetrode, gm ≤ 1.2 mS, μ ≤ 400, 150 V anode, 2 V/180 mA filament, A4A European 4-pin base and top terminal
  • B262 = M-OV/GEC S22 – Screen grid tetrode, gm = 1.3 mS, μ = 500, 150 V anode, 2 V/180 mA filament, A4A European 4-pin base and top terminal
  • B403 – AF Power triode, μ = 3, 50-150 V anode, 4 V/150 mA filament, A4A European 4-pin base
  • B405 – AF Power triode, μ = 5, 50-150 V anode, 4 V/150 mA filament, A4A European 4-pin base
  • B406 = Mullard PM4X = M-OV/GEC L410 – AF Power triode, μ = 6, 50-150 V anode, 4 V/100 mA filament, A4A European 4-pin base
  • B409 = LaRadiotechnique TB09 = M-OV/GEC P410 = Telefunken RE134 = Tungsram L414/L415 = Valvo L413 – AF Power triode, μ = 9, 250 V anode, 4 V/150 mA filament, A4A European 4-pin base
  • B424 = Mullard PM3D – AF Power triode, μ = 24, 200 V anode, 4 V/100 mA filament, A4A European 4-pin base
  • B438 = Valvo W410 – AF Power triode, μ = 38, 200 V anode, 4 V/100 mA filament, A4A European 4-pin base
  • B442 = CdL DZ2 = LaRadiotechnique TB42=R81 = Valvo H410D – Screen grid tetrode, gm = 900 µS, μ = 350, 200 V anode, 4 V/100 mA filament, A4A European 4-pin base and top terminal
  • B443 = CdL DX3 = Cossor 415PT = LaRadiotechnique B443O = M-OV/GEC 425PT = Tungsram PP415 – Power pentode, gm = 1.3 mS, μ = 100, 50-150 V anode, 4 V/150 mA filament, A4A European 4-pin base
  • B443S = Telefunken RES164 = Tungsram PP416 – Power pentode, gm = 1.4 mS, μ = 70, 200 V anode, 4 V/150 mA filament, O5A European 5-pin base
  • B543 – Power pentode, gm = 1.3 mS, μ = 60, 200 V anode, 5 V/100 mA filament, O5A European 5-pin base
  • B2006 = LaRadiotechnique CT06 = Telefunken REN1822 = Tungsram P2018 = Valvo L2218 – Power triode, μ = 6, 200 V anode, 20 V/180 mADC series heater, O5A European 5-pin base
  • B2038 = Telefunken REN1821 = Tungsram R2018 = Valvo A2118 – Triode, μ = 33, 200 V anode, O5A European 5-pin base; E438 with a 20 V/180 mADC series heater
  • B2041 = Telefunken REN1817D = Tungsram DG2018 = Valvo U1718D – Dual-grid triode for use as mixer (technically a tetrode), 100 V anode, 20 V/180 mADC series heater, O5A European 5-pin base with one grid on a lateral screw terminal
  • B2042 = Telefunken RENS1820 = Valvo H2018D – Sharp-cutoff RF/IF screen grid tetrode, gm = 1 mS, μ = 400, 100 V anode on top terminal, 20 V/180 mADC series heater, O5A European 5-pin base
  • B2043 = Telefunken RENS1823D = Tungsram PP2018D = Valvo L2318D – Power pentode, gm = 1.7 mS, μ = 70, 200 V anode, 20 V/180 mADC series heater, O5A European 5-pin base with the screen grid on a lateral screw terminal
  • B2044 = LaRadiotechnique CT44 = Mullard SD20 = Telefunken RENS1854 = Tungsram DS2218 = Valvo AN2127 – Diode + tetrode, gm = 2.8 mS, μ = 700, 200 V anode on top terminal, B6H European 6-pin base; E444 with a 20 V/180 mADC series heater
  • B2044S = Telefunken REN1826 – Diode + AF triode, μ = 30, 200 V anode, 20 V/180 mADC series heater, O5A European 5-pin base with diode on top terminal
  • B2045 = Telefunken RENS1819 – Remote-cutoff RF/IF screen grid tetrode, gm ≤ 1 mS, μ ≤ 400, 200 V anode on top terminal, 20 V/180 mADC series heater, O5A European 5-pin base
  • B2046 = Telefunken RENS1884 = Tungsram HP2018 = Valvo H2518D – RF/IF Pentode, gm = 2.2 mS, μ = 5000, 200 V anode on top terminal, 20 V/180 mADC series heater, O5A European 5-pin base
  • B2047 = Telefunken RENS1894 = Mullard VP20 = Tungsram HP2118 = Valvo H2618D – Remote-cutoff RF/IF pentode, gm ≤ 2 mS, μ ≤ 2000, 200 V anode on top terminal, 20 V/180 mADC series heater, O5A European 5-pin base
  • B2048 = Telefunken RENS1824 = Tungsram MH2018 = Valvo X2818 – Sharp-cutoff hexode mixer, 200 V anode, 20 V/180 mADC series heater, C7H European 7-pin base
  • B2049 = Telefunken RENS1834 = Valvo X2918 – Remote-cutoff hexode mixer, 200 V anode, 20 V/180 mADC series heater, C7H European 7-pin base
  • B2052T = Mullard SG20 = Telefunken RENS1818 = Valvo H1818D – Sharp-cutoff RF/IF tetrode, 250 V anode on top terminal, 20 V/180 mADC series heater, O5A European 5-pin base
  • B2099 = Telefunken REN1814 – AF Triode, μ = 99, 200 V anode, 20 V/180 mADC series heater, O5A European 5-pin base
  • C142 = Valvo H125D – Screen grid tetrode, gm = 1 mS, μ = 150, 50-150 V anode on top terminal, 1 V/250 mA filament, A4A European 4-pin base
  • C243N – Power pentode, gm = 2.4 mS, μ = 100, 150 V anode, 2 V/200 mA filament, O5A European 5-pin base
  • C405 = Tungsram P430 – AF Power triode, μ = 5, 250 V anode, 4 V/300 mA filament, A4A European 4-pin base
  • C443 = LaRadiotechnique TC43 = Telefunken RES364 = Tungsram PP430 = Valvo L425D – Power pentode, gm = 1.7 mS, μ = 60, 300 V anode, 4 V/250 mA filament, A4A European 4-pin base with lateral screw terminal; optionally O5A European 5-pin base
  • C443N = Mullard PM24DC = Telefunken RES374 = Tungsram PP431 = Valvo L427D – Power pentode, gm = 1.4 mS, μ = 50, 300 V anode, 4 V/250 mA filament, O5A European 5-pin base
  • C443N (Serie 250) – μ = 32
  • C453 – Slightly changed or only renamed C443
  • C509 = American 01-A – AF Power triode, μ = 9, 20-120 V anode, 4.5-5.3 V/250 mA filament, American UX4 4-pin base for use in imported radios with a rheostat filament supply for a 3-cell lead-acid battery; optionally A4A European 4-pin base
  • D143 = Valvo L160D – Power pentode, gm = 1.8 mS, μ = 100, 50-150 V anode, 1 V/650 mA filament, A4A European 4-pin base
  • D404 = Mullard AC044X = Telefunken RE604 = Tungsram P460 = Valvo LK460 – AF Power triode, μ = 3.5, 250 V anode, 4 V/650 mA filament, A4A European 4-pin base
  • E406 – AF Power triode, μ = 6, 150-250 V anode, 4 V/1 A filament, A4A European 4-pin base
  • E408 – AF/Modulator power triode, μ = 8, 200-400 V anode, 4 V/900 mA filament, A4A European 4-pin base
  • E408N = Telefunken RE614 – AF Power triode, μ = 8, 400 V anode, 4 V/1 A filament, A4A European 4-pin base
  • E409 = LaRadiotechnique TE09 = Valvo L4100 – AF Power triode, μ = 9, 200 V anode, 4 V/1 A heater, O5A European 5-pin base
  • E414 – AF Triode, μ = 14, 200 V anode, 4 V/1 A heater, A4A European 4-pin base
  • E415 = Telefunken REN804 = Valvo A4100/H4100 – AF Triode, μ = 15, 50-150 V anode, 4 V/900 mA heater, A4A European 4-pin base
  • E424 = LaRadiotechnique TE24 – AF Triode, μ = 24, 200 V anode, 4 V/1 A heater, O5A European 5-pin base; optionally A4A European 4-pin base with lateral screw terminal
  • E424N = E428 = LaRadiotechnique TE24N = Telefunken REN904 = Tungsram AG495 – AF Triode, μ = 28, 200 V anode, 4 V/1 A heater, O5A European 5-pin base
  • E430 – AF Triode, μ = 30, 50-150 V anode, 4 V/1 A heater, O5A European 5-pin base; optionally A4A European 4-pin base with lateral screw terminal
  • E435 – AF Triode, μ = 35, 50-150 V anode, 4 V/900 mA heater, O5A European 5-pin base; optionally A4A European 4-pin base with lateral screw terminal
  • E438 = Telefunken REN1004 = Valvo W4080/W4100 – Triode, μ = 38, 200 V anode, O5A European 5-pin base; B2038 with a 4 V/1 A heater
  • E441 = CdL DW1 = Tungsram DG4101 = Valvo U4100D, E441N = Telefunken REN704D – Dual-grid triode used as mixer (technically a tetrode), 100 V anode, 4 V/900 mA heater, O5A European 5-pin base with first grid on a lateral screw terminal
  • E442 = Valvo H4100D – RF/IF Screen grid tetrode, gm = 900 µS, μ = 700, 150-200 V anode, 4 V/900 mA heater, O5A European 5-pin base and top terminal
  • E442S = Cossor 41MSG = Telefunken RENS1204 = Valvo H4080D – RF/IF Screen grid tetrode, gm = 1 mS, μ = 400, 200 V anode, 4 V/1 A heater, O5A European 5-pin base and top terminal
  • E443 – Power pentode, gm = 1.8 mS, μ = 60, 300-400 V anode, 4 V/900 mA filament, O5A European 5-pin base
  • E443H = LaRadiotechnique TE43H = Telefunken RES964 = Tungsram PP4101 = Valvo L496D = Fivre RTP4 – Power pentode, gm = 3 mS, μ = 130, 250 V anode, 4 V/1.1 A filament, O5A European 5-pin base
  • E443N = LaRadiotechnique TE43N = Tungsram PP4100 = Valvo L491D – Power pentode, gm = 1.9 mS, μ = 75, 400 V anode, 4 V/900 mA filament, O5A European 5-pin base
  • E444 = LaRadiotechnique TE44/TE444 = Telefunken RENS1254 = Tungsram DS4100 = Valvo AN4126 – Diode + tetrode, B6H European 6-pin base; B2044 with a 4 V/1.1 A heater
  • E444S = LaRadiotechnique TE44S = Telefunken REN924 = Valvo AN4092 – Diode + AF triode, μ = 30, 4 V/1 A heater, O5A European 5-pin base
  • E445 = LaRadiotechnique TE45 = M-OV/GEC VMS4 = Mullard VM4V = Telefunken RENS1214 = Tungsram AS4104 = Valvo H4125DSelektode, a remote-cutoff RF/IF screen grid tetrode, gm ≤ 1 mS, μ ≤ 300, 200 V anode, 4 V/1 A heater, O5A European 5-pin base and top terminal
  • E446 = Cossor MS/Pen = LaRadiotechnique TE46 = Mullard SP4 = Telefunken RENS1284 = Tungsram HP4100/HP4101 = Valvo H4128D – RF Pentode, gm = 2.5 mS, μ = 5000, 200 V anode, 4 V/1.1 A heater, O5A European 5-pin base and top terminal
  • E447 = LaRadiotechnique TE47 = M-OV/GEC VMP4 = Telefunken RENS1294 = Tungsram HP4106 = Valvo H4129D – Remote-cutoff RF pentode, gm ≤ 2 mS, μ ≤ 2000, 200 V anode, 4 V/1.1 A heater, O5A European 5-pin base and top terminal
  • E448 = LaRadiotechnique TE48 = Telefunken RENS1224 = Tungsram MH4100 = Valvo X4122 – Sharp-cutoff hexode mixer, 200 V anode, 4 V/1.2 A heater, C7H European 7-pin base and top cap
  • E449 = LaRadiotechnique TE49 = Telefunken RENS1234 = Tungsram FH4105 = Valvo X4123 – Remote-cutoff hexode mixer, 4 V/1.2 A heater, C7H European 7-pin base and top cap
  • E452T = LaRadiotechnique TE52 = Telefunken RENS1264 = Valvo H4111D – Rcreen grid tetrode, gm = 2 mS, μ = 900, 200 V anode, 4 V/1 A heater, O5A European 5-pin base and top terminal
  • E453 = LaRadiotechnique TE53/TE534 = Telefunken RENS1374D = Tungsram APP4100 = Valvo L4150D – Power pentode, gm = 2.5 mS, μ = 175, 250 V anode, 4 V/1.1 A heater, O5A European 5-pin base
  • E455 = LaRadiotechnique TE55 = Mullard MM4V = Telefunken RENS1274 = Valvo H4115D – Remote-cutoff RF pentode, gm ≤ 2 mS, μ ≤ 700, 200 V anode, 4 V/1 A heater, O5A European 5-pin base and top terminal
  • E462 = LaRadiotechnique TE424 = Tungsram AS495 – Sharp-cutoff RF pentode, gm = 2 mS, μ = 900, 200 V anode, 4 V/1 A heater, O5A European 5-pin base and top terminal
  • E463 = LaRadiotechnique TE63 = Mullard ME463 = Telefunken RENS1384 = Tungsram APP4130 = Valvo L4138D – Power pentode, gm = 2.7 mS, μ = 100, 250 V anode, 4 V/1.35 A heater, B6H European 6-pin base
  • E499 = Telefunken REN914 = Valvo W4110 – AF Triode, μ = 99, 200 V anode, 4 V/1 A heater, O5A European 5-pin base
  • F215 (Valvo A2200W) – Triode, μ = 15, 20-150 V anode, 2.5 V/1.5 A heater, A4A European 4-pin base with the cathode on a lateral terminal
  • F410 = Valvo LK4200 – Power triode, μ = 10, 400-550 V anode, 4 V/2 A filament, A4A European 4-pin base
  • F443 = Valvo L495D – Power pentode, gm = 3 mS, μ = 100, 550 V anode, 4 V/2 A filament, O5A European 5-pin base
  • F443N = Valvo L497D – Power pentode, gm = 3.9 mS, μ = 80, 300 V anode, 4 V/2 A filament, O5A European 5-pin base
  • F704 – AF/Modulator power triode, μ = 3.8, 400-450 V anode, 7.5 V/1.25 A filament, A4A European 4-pin base or American UX4 base for use in imported devices
  • F708 (American 10 = CX-310 = UX-210) – AF/Modulator power triode, μ = 8, 250-450 V anode, 7.5 V/1.25 A filament, A4A European 4-pin base

The Milan branches of Philips and Siemens-Telefunken sold Philips and M-P tubes on the Italian market, some modified:

  • WE11 – EBC3
  • WE12 – EM4
  • WE13 – ECL11 w/P8A base
  • WE14 = EL6
  • WE15 = EL3N
  • WE16 – EF11 w/P8A base
  • WE17 – EF6
  • WE18 = EFM1
  • WE19 – EBF2
  • WE20 – ECH11 w/P8A base
  • WE21 = AK1
  • WE22 = WE40 = ACH1
  • WE23 = E446 = RENS1284
  • WE24 = E447 = RENS1294
  • WE25 – (AF2)
  • WE26 = E444 = RENS1254
  • WE27 = E424N = REN904
  • WE28 = E499 = REN914
  • WE29 = E444S = REN924
  • WE30 = E443H = RES964
  • WE31 = AB1
  • WE32 = AK2
  • WE33 = AF3
  • WE34 = AF7
  • WE35 = AL1
  • WE36 = AB2
  • WE37 = ABC1
  • WE37F – ABF1
  • WE38 = AL4
  • WE39 = AC2
  • WE41 = ABL1
  • WE42 = AL5
  • WE43 = ACH1C
  • WE44 – Triode+hexode
  • WE51 = 1805 = RGN1064
  • WE52 = 1561 = RGN2004
  • WE53 = AZ2
  • WE54, WE55 – AZ1
  • WE56 = AZ4
  • WE65 – Full-wave rectifier
Professional tubes

Philips used a 4/5-digit system for professional/industrial/telecommunications tubes, which they phased out in the 1960s in favor of PE Professional tubes:

  • 1000 to 1899 – Rectifier

Examples:

  • 1063A – 3-Phase, half-wave, Argon/Mercury-vapor Tungar bulb, a low-voltage rectifier for charging 90-cell lead-acid batteries at 6 A per phase, 1.9 V/11 A filament
  • 1069K – Forced-air cooled, full-wave Tungar bulb used in 60 A DC welding power supplies, 3.25 V/70 A filament
  • 1533A – 3-Phase, half-wave, Argon/Mercury-vapor Tungar bulb, a low-voltage rectifier for charging 110-cell lead-acid batteries at 15 A per phase, 1.9 V/23 A filament
  • 1543A – 3-Phase, half-wave, Argon/Mercury-vapor Tungar bulb, a low-voltage rectifier for charging 110-cell lead-acid batteries at 25 A per phase, 1.9 V/36 A filament
  • 1553A – 3-Phase, half-wave, Argon/Mercury-vapor Tungar bulb, a low-voltage rectifier for charging 110-cell lead-acid batteries at 40 A per phase, 1.9 V/70 A filament
  • 1561 = Telefunken RGN2004 – 1.4 kV, 2×80 mA Full-wave rectifier, 4 V/2 A filament; AZ2 with an A4A European 4-pin base
  • 1805 = RGN1064 – 1.4 kV, 2×50 mA Full-wave rectifier, 4 V/1 A filament, A4A European 4-pin base
  • 1927 (40 to 120 V filament for 110VDC mains), 1928 (80 to 240 V filament for 220VDC mains) – Barretters for use with 180mADC tube sets[9]
  • 3520 – Early 3-stage, S1 photomultiplier, side-contact 8 base
  • 4000s – See below
  • 18042 = 6086 – Pentode used in telephone equipment, 18 V/100 mA heater, Noval base
  • 18503 = ZP1200
  • 18504 = ZP1400
  • 18505 = ZP1410
  • 18506 = ZP1431
  • 18507 = ZP1600
  • 18509 = ZP1310
  • 18511 = ZP1610
  • 18515 = ZP1441
  • 18518 = ZP1700
  • 18520 = ZP1210
  • 18525 = ZP1520
  • 18526 = ZP1430
  • 18529 = ZP1300
  • 18536 = ZP1451
  • 18545 = ZP1220
  • 18546/01 = ZP1460
  • 18550 = ZP1320
  • 18555 = ZP1330
  • 56001 – Directly heated, 300 V, 400 µA thermally-limited (=saturated) emission diode, 4.6 V/163 mAmax filament, usable as a heating current-controlled, variable series resistor in voltage/current stabilizer circuits, or as an RMS heating current-to-DC anode current converter; cf. 5845, Tesla RA0007, YA1000
  • 56006Omegatron Mass spectrometer tube. An electron gun sends an electron beam through a cavity to an electron collector anode. The cavity contains the gas to be analyzed. The gas is ionized by the electron beam and a magnetic field parallel to the axis of the beam forces the gas ions into a helical path around the beam, the orbital angular velocity depending on the ion mass. An electrode inside the cavity floods it with an RF electric field perpendicular to the magnetic field, from a sweep generator. When the frequency matches an ion's angular velocity, that ion will resonate and spiral outward like in a cyclotron, eventually hitting an ion collector electrode and generating a current there, which is amplified and measured[88]

Philips used more freeform designations for thyratrons and ignitrons; examples are:

  • PL5 – 1.5 kV, 3.5 Aavg, 100 Apeak Sendytron,(de) a Mercury-vapor thyratron with an auxiliary anode and capacitive ignition by an isolated control rod dipping into the cathode pool[89][90]
  • PL10 – 400 V, 100 mAavg, 4 Apeak Mercury-vapor thyratron with external capacitive ignition
  • PL17 = PL5557 = 5557 – 2.5 kV, 500 mAavg, 2 Apeak Mercury-vapor thyratron
  • PL21 = PL2D21 = 2D21 = EN91 – 650 V, 100 mAavg, 500 mApeak, 10 Asurge, Xenon-filled, indirectly heated tetrode thyratron used as relay driver or grid-controlled rectifier, negative starter voltage, Miniature 7-pin base
  • PL57 = PL5559 = 5559 – 1 kV, 2.5 Aavg, 15 Apeak Mercury-vapor thyratron
  • PL323 = PL3C23 = 3C23 – 1.25 kV, 1.5 Aavg, 6 Apeak Argon/Mercury-vapor triode thyratron, UX4 base with anode on top cap
  • PL435 = PL4C35 = 4C35, PL522 = PL5C22 = 5C22 – Half-indirectly heated, Hydrogen triode thyratrons used in radar modulators, B4D Superjumbo base with anode on top cap
  • PL2952A, PL5553B = 5553B – Water-cooled Ignitrons used in DC welding power supplies
  • PL5551 = 5551, PL5552 = 5552, PL5882 = 5882 – Water-cooled Ignitrons used in resistance welding power supplies
  • PL5555 = 5555 – Water-cooled Ignitron used as AC control or controlled rectifier
  • PL5727 = 5727 – Ruggedized PL21
  • PL5822 = 5822 – Water-cooled Ignitron used in frequency changer welding power supplies

Media related to Philips vacuum tubes at Wikimedia Commons

Media related to Philips gas discharge tubes at Wikimedia Commons

Basing code

From 1924 to 1939, Philips printed a basing code on tube cartons and price lists, but not on the tubes themselves.[46]: 228  Socket designations such as "A-type" or "P-base" refer to this code, which was later (1950s) expanded to a <BasingCode><PinCount><Variant> format (where new designs were assigned the default basing codes "B" for normal tubes and "X" for microwave tubes):

  • A – 4-pin Transcontinental European base, originally Franco-British
  • B – 4-pin Telefunken base (1920s);[85]: 16f  later 6-pin Continental European base (1930s)[3]: 15 
  • C – American UV base (1920s); later 7-pin Continental European base (1930s)
  • D – 5-pin French base, used on bi-grille tetrodes
  • E – 4-pin French Radiola base (1920s); later Medium 7-pin American U7A base (1930s)
  • F – 4-stub American UV-199-type base
  • G – 4-pin American UX4 base
  • H – 3-pin European base
  • J – 6-pin American U6A base
  • K – Octal base
  • L – 5-pin Special base[91]: 91 
  • M – 4-pin American WD-11-type base (1920s); later 7-pin British base (1930s)
  • N – 5-pin American UY5 base
  • O – 5-pin Transcontinental European base
  • P – Side-contact 8 base
  • Q – 7-pin Special base[91]: 91 
  • R – 9-pin British base[91]: 91 
  • SMidget 4-pin Hivac subminiature hearing aid base[91]: 91 
  • T – 9-pin all-glass Continental European base
  • U – 6-pin Special base[91]: 90 
  • V – Side-contact 5 base
  • W – 4-pin Special base[91]: 91 
  • XAcorn tube
  • Y – 8-pin Continental European base, originally German steel tubes a.k.a. "German Metal Octal"

On cartons and tube lists, this basing code was followed by a number giving the maximum envelope diameter in mm

STC systems

"Brimar" standard tubes

For their Brimar ("British Manufactured American Radio" [tubes]) brand, WE-STC used the following scheme until the 1950s, when they phased it out in favor of the RETMA, EIA and Mullard–Philips systems:[18]

  • A number: Function/type
  • 1 – Half-wave rectifier
  • 2 – Diode
  • 3 – Power triode
  • 4 – High-μ triode
  • 5 – Sharp-cutoff tetrode
  • 6 – Remote-cutoff tetrode
  • 7 – Power or video pentode
  • 8 – Sharp-cutoff RF pentode
  • 9 – Remote-cutoff RF pentode
  • 10 – Dual diode
  • 11 – Dual diode + triode
  • 12 – Dual diode + AF pentode
  • 13 – Dual high-μ triode
  • 14 – Dual Class-B power triode
  • 15 – Heptode
  • 16 – DC-coupled power triode
  • 17 – Dual diode + RF pentode
  • 18 – Triode + pentode
  • 20 – Triode/hexode or triode/heptode oscillator/mixer
  • A letter: Filament/heater rating
  • A – 4 V, Indirectly heated
  • B – 2 V, Directly heated
  • C – Other directly heated
  • D – Other indirectly heated
  • A sequentially assigned number

Examples:

  • 1D5 – Half-wave rectifier; 25Z4-G with a 40 V/200 mA heater and an O5A European 5-pin base (not to be confused with the RETMA 1D5 remote-cutoff pentode)
  • 1D6 – Half-wave rectifier; 25Z4-G with a U6A American 6-pin base
  • 4D1 – Triode, 13 V/200 mA heater, M7A British 7-pin base
  • 7A2 – Power pentode, 4 V/1.2 A heater, M7A British 7-pin base
  • 7A3 = Cossor 42MP/PEN = EdiSwan AC2/PEN = Ferranti PT4 = Mullard PEN4VB – Power pentode, 4 V/2 A heater, M7A British 7-pin base
  • 7D3 – Power pentode, 40 V/200 mA heater, M7A British 7-pin base
  • 7D6 – Power pentode, 40 V/200 mA heater, M7A British 7-pin base
  • 7D8 – Power pentode, 13 V/650 mA heater, M7A British 7-pin base
  • 7D10 = 6CH6/EL821 – Power pentode, 6.3 V/750 mA heater, Noval base
  • 8A1 = Cossor MS/PEN = EdiSwan AC/S2PEN = Ferranti SPT4 = M-OV/GEC MSP4 – Sharp-cutoff pentode, 4 V/1 A heater, O5A European 5-pin base
  • 8D2 – Sharp-cutoff pentode, 13 V/200 mA heater, M7A British 7-pin base
  • 8D3 = 6AM6/EF91 – Sharp-cutoff pentode, 6.3 V/300 mA heater, Miniature 7-pin base
  • 8D5 = 6BR7, 8D8 – Low-hum, low-microphonics, sharp-cutoff pentodes, 6.3 V/150 mA heater, Noval base
  • 9A1 = Cossor MVS/PEN = EdiSwan AC/VP1 = Ferranti VPT4 = M-OV/GEC VMP4 = Mullard VP4 – Remote-cutoff RF/IF pentode, 4 V/1 A heater, O5A European 5-pin base with anode on top cap
  • 9D2 – Remote-cutoff RF/IF pentode, 13 V/200 mA heater, M7A British 7-pin base with grid on top cap
  • 9D6 – Remote-cutoff RF/IF pentode, 6.3 V/200 mA heater, Miniature 7-pin base
  • 9D7 – Remote-cutoff RF/IF pentode, 6.3 V/300 mA heater, Noval base
  • 10D1 – Common cathode dual diode, 13 V/200 mA heater, O5A European 5-pin base
  • 11A2 = Cossor DDT = EdiSwan AC/HLDD = M-OV/GEC MHD4 = Mullard TDD4 – Common cathode dual diode + triode, 4 V/1 A heater, M7A British 7-pin base
  • 11D3 – Common cathode dual diode + triode, 13 V/200 mA heater, M7A British 7-pin base
  • 11D5 – Common cathode dual diode + triode, 13 V/150 mA heater, M7A British 7-pin base
  • 13D1 = 25SN7-GT, 13D2 = 6SN7-GT – Separate cathodes, dual triodes, Octal base
  • 13D3 (CV2212) – Separate cathodes, dual triode, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base
  • 13D7 = ECC807 – Separate cathodes, dual triode, 6.3 V/300 mA heater, Noval base
  • 13D8 (12AU7/ECC82) – Separate cathodes, dual AF triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • 13D9 – Separate cathodes, dual triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • 15A2 = Cossor 41MPG = Ferranti VHT4 = M-OV/GEC MX40 (4 V/650 mA heater), 15D1 (13 V/200 mA heater), 15D2 (13 V/150 mA heater) – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, M7A British 7-pin base
  • 20A1 – Triode/heptode oscillator/mixer, 4 V/1.2 A heater, M7A British 7-pin base
  • 20D2 – Triode/hexode oscillator/mixer, 13 V/150 mA heater, M7A British 7-pin base
  • 20D4 – Triode/heptode oscillator/mixer, 6.3 V/300 mA heater, Noval base
Professional tubes

Besides their "4000" system with incorporated Western Electric 3-digit type numbers (examples), STC used the following system:[92]

  • An optional preceding "L." indicates a special quality version
  • An optional digit: Electrode count
    Note: Dual-system tubes, such as dual triodes or full-wave rectifiers, are assigned two digits
  • 2 – Diode
  • 3 – Triode
  • 4 – Tetrode
  • 5 – Beam tetrode or pentode
  • A letter: Type, fill gas or cooling method
  • A – Anode dissipation below 10 W
  • B – Anode dissipation 10...100 W
  • C – Anode dissipation 100...1000 W
  • D – Anode dissipation 1 kW or more
  • G – Gas-filled
  • H, J – Forced-air cooled, glass/metal envelope
  • HC, JC – Forced-air cooled, ceramic/metal envelope
  • K – Contact/conduction cooled
  • P – Pulse-rated
  • Q – Water-cooled
  • R – Helix or other integral cooler
  • S – Low voltage rectifier
  • T – High voltage rectifier
  • V – Mercury-vapor filled
  • Z – Water/vapor-cooled
  • An optional number if none preceded the letter (notably with cold-cathode tubes):
    Gas-filled trigger tubes: Max. ignition voltage
    Voltage-regulator tubes: Burning voltage
  • A slash followed by a number:
    High-vacuum tubes: 2-digit power rating followed by a sequentially assigned digit
  • A letter: Base
  • A – American base
  • B – British base
  • C – Edison screw base
  • D – Octal base
  • E – Special base
  • G – Wire-ends
  • J – Disk-seal tube
  • K – Miniature base
  • M – B8F Eimac/JEDEC B8-236 9-pin blow-through base
  • An optional letter Y: Tightened specs

Examples:

  • 3J-187E (Glass/metal), 3JC-187E (ceramic/metal) – Forced-air cooled power triode
  • 3RM-215G – 10 MHz, 8 kW, Water/helix-cooled Neotron, used as RF power amplifier or oscillator; similar to YD1352S/8867
  • 4G/280K = 2D21/EN91 – 650 V, 100 mAavg, 500 mApeak, 10 Asurge, Xenon-filled, indirectly heated tetrode thyratron used as relay driver or grid-controlled rectifier, negative starter voltage, Miniature 7-pin base
  • 22V/310A – 1.4 kV, 250 mA Full-wave Mercury-vapor rectifier
  • G10/241ENomotron, a unidirectional Dekatron with multi-alloy cathodes
  • G75/2D = 0A3 = M-OV/GEC QS75/40 – 75 V Voltage-regulator tube, Octal base
  • P535-1E = WE 715B (15 kV), P552-1E = 5D21 (20 kV) – Pulse-rated power tetrodes used in hard-tube pulser radar modulators

Valvo system before 1934

Valvo(de, it) was a major German electronic components manufacturer from 1924 to 1989; a Philips subsidiary since 1927, Valvo was one of the predecessors of NXP Semiconductors.

The system consisted of one or two letters followed by 3 or 4 digits. It was phased out after 1934 when Valvo adopted the Mullard–Philips scheme.

  • Letter(s): Function/type[93]
  • A – Triode
  • ANBinode, a diode+triode or diode+tetrode
  • G – Rectifier
  • H – RF tube
  • L – Power tube
  • LK – Power amplifier
  • USpace charge grid tetrode (the 2nd grid is the control grid)
  • W – Triode for resistor-coupled amplifiers
  • X – Hexode
  • A number: Filament/heater rating:
  • If the first digit is 4, the tube has a 4 V heater
  • Otherwise, the last two digits give the heater current in tens of mA.
  • A following letter D indicates more than one grid, not counting a space charge grid

Examples:[87]

  • A2118 = B2038 = REN1821 = R2018 – Triode, 180 mA (=18 × 10 mA) heater, O5A European 5-pin base
  • H2018D = B2042 = RENS1820 = S2018 – RF Tetrode or pentode, 180 mA heater, O5A European 5-pin base
  • L496D = E443H = RES964 = PP4101 = RTP4 = P435 – Power pentode, 4 V/1.1 A filament with suppressor grid on center tap, O5A European 5-pin base
  • L2318D = B2043 = RENS1823D = PP2018D – Power pentode, 180 mA heater, O5A European 5-pin base with screen grid on side screw

Media related to Valvo vacuum tubes at Wikimedia Commons

Media related to Valvo gas discharge tubes at Wikimedia Commons

East European systems

Lamina transmitting tubes system

Polish Lamina(pl) transmitting tube designations consist of one or two letters, a group of digits and an optional letter and/or two digits preceded by a "/" sign.

  • A letter: Function/type:
    Note: Two equal letters indicate a dual-system tube
  • P – Pentode
  • Q – Tetrode
  • T – Triode
  • A number: Maximum anode power dissipation in kW
  • An optional letter: Cooling method:
  • <none> – Radiation
  • P – Forced-air
  • W – Water
  • A slash followed by a digit:
  • 1 – Tube for radio broadcasting and radiocommunication equipment
  • 2 – Tube for industrial equipment
  • 3 – Tube used in analog TV broadcasting equipment
  • 4 – Tube for radiocommunication equipment with unbalanced modulation
  • 5 – Modulator or pulse-rated tube
  • A sequentially assigned digit

Examples:

  • Q01 – 125 MHz, 0.1 kW (=100 W) Power tetrode
  • Q3.5 – 220 MHz, 3.5 kW Power tetrode
  • QQ-004/11 – 500 MHz, 0.04 kW (=40 W) Dual beam power tetrode
  • T01 – 200 MHz, 135 W Power triode
  • T015/21 – 150 MHz, 150 W Power triode
  • T02 – 60 MHz, 200 W Power triode
  • T05P/31 – 1 GHz, 1 kW Forced-air cooled power triode
  • T2/22 – 60 MHz, 3 kW Power triode
  • T6 – 30 MHz, 6 kW Power triode
  • T8P/21 – 120 MHz, 8 kW Forced-air cooled power triode
  • T10P/22 – 30 MHz, 10 kW Power triode
  • T-25P – 30 MHz, 25 kW Forced-air cooled power triode
  • T60W/21 – 30 MHz, 6 kW Water-cooled power triode

Media related to Lamina vacuum tubes at Wikimedia Commons

Media related to Lamina gas discharge tubes at Wikimedia Commons

RFT systems

Rundfunk- und Fernmelde-Technik(de, sv) was the brand of a group of telecommunications manufacturers in the German Democratic Republic. RFT used the Mullard–Philips and RETMA schemes for their signal and low-power tubes.

Transmitting tubes

The designation consists of 3 letters and a 3 or 4-digit number

  • Two letters: Function/type acronym:
  • A third letter: Cooling method acronym:
  • A number: Electrode count:
    Note: Two equal digits indicate a dual-system tube
  • 2 – Diode
  • 3 – Triode
  • 4 – Tetrode
  • 5 – Pentode
  • Two sequentially assigned digits

Examples:

  • GRS251 – Radiation-cooled 25 kV/300 mA rectifier
  • SRL/W314 – 12 kW, 30 MHz Forced-air or water-cooled power triode
  • SRL364 – 14 kW, 175 MHz Forced-air cooled power triode
  • SRL458 – 10 kW, 790 MHz Forced-air cooled power tetrode
  • SRL462 – 25 kW, 30 MHz Forced-air cooled power tetrode
  • SRS301 – 900 W, 40 MHz Radiation-cooled power triode
  • SRS362 – 1.25 kW, 100 MHz Radiation-cooled power triode
  • SRS401 – 1 kW, 120 MHz Radiation-cooled power tetrode
  • SRS464 – 300 kW Ruggedized, pulse-rated, radiation-cooled power tetrode
  • SRS4451 – 60 W, 500 MHz Radiation-cooled dual power tetrode
  • SRS4452 = QQE03/20 = 6252 – 20 W, 200 MHz Radiation-cooled dual power tetrode
  • SRS4453 – Pulse-rated variant of type SRS4451
  • SRS501 – 100 W, 50 MHz Radiation-cooled pentode
  • SRS552N = ГУ-50 – 50 W, 120 MHz Radiation-cooled pentode
  • SRV355 – 50 kW, 30 MHz Water/vapor-cooled power triode
  • SRW353 – 15 kW, 220 MHz Water-cooled power tetrode
  • VRS303 – 1 kW Radiation-cooled AF power triode
  • VRS328 – 150 W Radiation-cooled AF power triode
  • VRS331 – 450 W Radiation-cooled AF power triode
Microwave tubes
  • A function/type acronym:
  • A sequentially assigned number, the first one or two digits of which give the frequency in GHz.

Media related to RFT vacuum tubes at Wikimedia Commons

Tesla systems

Signal and low-power tubes

Besides the genuine Mullard–Philips system, Tesla also used an M-P/RETMA hybrid scheme:[18]

  • A number: Filament/heater voltage, as in the RETMA system
  • Letter(s): Function/type, subset of the Mullard–Philips system
  • A digit: Base
  • 1 – K8A Octal
  • 2 – B8G Loctal
  • 3 – B7G Miniature 7-pin
  • 4 – B9A Noval
  • 5 – Special, mostly 9 out of 10 1.25mm pins on a 25mm-diameter circle
  • 6 – B11A Submagnal
  • 7 – B12A Duodecal
  • 8 – B14A Diheptal
  • 9 – Wire-ends
  • A sequentially assigned digit

Examples:

  • 1AF33 = 1AH5/DAF96 (1.4 V/25 mA filament), 1AF34 (1.2 V/30 mA filament) – Diode + AF pentode, Miniature 7-pin base
  • 1F33 = 1AJ4/DF96 (1.4 V/25 mA filament), 1F34 (1.2 V/30 mA filament) – Remote-cutoff RF/IF pentode, Miniature 7-pin base
  • 1H33 = 1R5-SF = 1AQ5 (=1R5/DK91 with a 1.4 V/25 mA filament), 1H34 (1.2 V/30 mA filament) – Heptode pentagrid converter with American grid topology, anode voltage in the 45...90 volt range, Miniature 7-pin base
  • 1H35 = 1AB6/DK96 – Heptode pentagrid converter with suppressor (#5) grid internally tied to the positive 1.4 V/25 mA filament end, Miniature 7-pin base
  • 1M90 = DM70/1M3 – Subminiature indicator tube, 1.4 V/25 mA filament, all-glass wire-ended
  • 1Y32 – CRT EHT rectifier, 1.4 V/265 mA thoriated Tungsten filament, Miniature 7-pin base
  • 1Y32T – 1Y32 with a wide-range, 1.19 V to 1.61 V oxide-coated filament
  • 3L31, 3L32 – Power pentodes, center-tapped 2.8 V/50 mA resp. 1.4 V/100 mA filament, Miniature 7-pin base
  • 4L20 = 4П1Л4P1L – 120 MHz Power pentode, center-tapped 4.2 V/325 mA resp. 2.1 V/650 mA filament; Telefunken RL4,2P6 with a Loctal base
  • 6B31, 6B32 = 6AL5/EAA91/EB91 = 6Х2П6H2P (Different pinout) – 700 MHz Dual diode, 6.3 V/300 mA heater, Miniature 7-pin base
  • 6BC32 = 6AV6/EBC91 – Dual diode + triode, 6.3 V/300 mA heater, Miniature 7-pin base
  • 6CC10 = 6SN7-GT – Dual triode, 6.3 V/600 mA heater, Octal base
  • 6CC31 = 6J6/ECC91 = 6H15П6N15P – 600 MHz Dual VHF triode, 6.3 V/450 mA heater, Miniature 7-pin base
  • 6CC42 = 2C51 = 6Н3П6N3P (5670) – Dual VHF triode, 6.3 V/350 mA heater, Noval base
  • 6F24 – Telecom pentode, 6.3 V/450 mA heater, Loctal base
  • 6F31 = 6BA6/EF93 – Remote-cutoff pentode, 6.3 V/300 mA heater, Miniature 7-pin base
  • 6F32 = 6AK5/EF95 = 6Ж1П6J1P – Sharp-cutoff pentode, 6.3 V/175 mA heater, Miniature 7-pin base
  • 6F35 = 6AJ5/6АЖ5 – Low (6.3-80 V) anode voltage, sharp-cutoff pentode, 6.3 V/175 mA heater, Miniature 7-pin base
  • 6F36 = 6AH6 = 6Ж5П6J5P – Sharp-cutoff IF/video pentode, 6.3 V/450 mA heater, Miniature 7-pin base
  • 6H31 = 6BE6/EK90 = 6А2П6A2P – Pentagrid converter, 6.3 V/300 mA heater, Miniature 7-pin base
  • 6L31 = 6AQ5/EL90 – Power pentode, 6.3 V/450 mA heater, Miniature 7-pin base
  • 6L41 = 5763 (6П1П6P1P) – Beam power tetrode, 6.3 V/750 mA heater, Noval base
  • 6L43 = 6CL6 – Power pentode used as CRT cathode driver, 6.3 V/650 mA heater, Noval base
  • 6L50 – VHF power pentode; derived from Telefunken/Luftwaffe LS50
  • 6Z31 = 6X4/6BX4/EZ90 = 6Ц4П6C4P – Full-wave rectifier, 6.3 V/600 mA heater, Miniature 7-pin base
  • 12BC32 = 12AV6/HBC91 – 6BC32 Dual diode + triode with a 12.6 V/150 mA heater, Miniature 7-pin base
  • 12F31 = 12BA6/HF93 – 6F31 Remote-cutoff pentode with a 12.6 V/150 mA heater, Miniature 7-pin base
  • 12H31 = 12BE6/HK90 – 6H31 Pentagrid converter with a 12.6 V/150 mA heater, Miniature 7-pin base
  • 35Y31 – Half-wave rectifier, 35 V/150 mA series heater; UY1(N) with Miniature 7-pin base
Transmitting tubes
  • A letter: Type:
  • R – Rectifier or RF tube
  • U – Gas-filled rectifier
  • Z – Modulator tube
  • Letter(s): Function, subset of the Mullard–Philips scheme
  • A number: Anode dissipation in W (if radiation-cooled) or kW (otherwise)
  • A letter: Cooling method:
  • <none> – Radiation
  • V – Water/vapor
  • X – Forced-air
  • Y – Water

Examples:

  • RA0007A (Octal base), RA0007B (Noval base) – 600 V, 700 µA Directly heated, thermally-limited (=saturated) emission diode, 1.4 V/3.5 Amax uncoated Tungsten filament, usable as a heating current-controlled, variable series resistor in voltage/current stabilizer circuits, or as an RMS heating current-to-DC anode current converter, or as a noise diode; cf. 5845, YA1000
  • RA025B – 20 kV, 250 mA Half-wave rectifier with an E40 Goliath Edison screw lamp base and an anode screw top cap
  • RA05A – 25 kV, 700 mA Half-wave rectifier with an E40 Goliath Edison screw lamp base and an anode screw top cap
  • RA7YB – 25 kV, 7 A Half-wave rectifier
  • RA100A – 40 kV, 100 mA Half-wave rectifier with an E40 Goliath Edison screw lamp base and anode on top cap
  • RC5B, RC5C – 5 W Pressed Cup-type UHF power triode
  • RD27AS – 27 W, 25 MHz Radiation-cooled power triode
  • RD200B – 200 W, 60 MHz Radiation-cooled power triode
  • RD300S – 300 W, 200 MHz Radiation-cooled power triode
  • RD1XB – 1 kW, 30 MHz Water-cooled power triode
  • RD1.5XA – 1.5 kW, 30 MHz Forced-air cooled power triode
  • RD2XF – 2 kW, 150 MHz Forced-air cooled power triode
  • RD3XL – 2 kW, 30 MHz Forced-air cooled power triode
  • RD5XF – 5 kW, 100 MHz Forced-air cooled power triode
  • RD5YA – 5 kW, 20 MHz Water-cooled power triode
  • RD8XA – 8 kW, 3 MHz Forced-air cooled power triode
  • RD12XB – 12 kW, 30 MHz Forced-air cooled power triode
  • RD12YB – 12 kW, 30 MHz Water-cooled power triode
  • RD18YA – 18 kW, 30 MHz Water-cooled power triode
  • RD20VL – 20 kW, 100 MHz Water/vapor-cooled power triode
  • RD20XF – 20 kW, 30 MHz Forced-air cooled power triode
  • RD50VL – 50 kW, 100 MHz Water/vapor-cooled power triode
  • RD50XA – 50 kW, 3 MHz Forced-air cooled power triode
  • RD50YA – 50 kW, 10 MHz Water-cooled power triode
  • RD75YB – 75 kW, 3 MHz Water-cooled power triode
  • RD150YA – 150 kW, 3 MHz Water-cooled power triode
  • RE40AK = KT88
  • RE65A – 65 W, 260 MHz Radiation-cooled beam power tetrode
  • RE125C – 125 W, 235 MHz Radiation-cooled beam power tetrode
  • RE400C – 400 W, 235 MHz Radiation-cooled beam power tetrode
  • RE1000F – 1 kW, 150 MHz Radiation-cooled beam power tetrode
  • RE041XL – 500 W, 250 MHz Forced-air cooled beam power tetrode
  • RE0125XL – 150 W, 500 MHz Forced-air cooled beam power tetrode
  • RE025XA – 250 W, 500 MHz Forced-air cooled beam power tetrode
  • RE1.5XL – 2 kW, 250 MHz Forced-air cooled beam power tetrode
  • RE5XL – 5 kW, 250 MHz Forced-air cooled beam power tetrode
  • RE20XL – 20 kW, 220 MHz Forced-air cooled beam power tetrode
  • REE30A – 20 W, 250 MHz Radiation-cooled dual beam power tetrode
  • RL15A – 20 W, 60 MHz Radiation-cooled power pentode
  • RL40A – 40 W, 120 MHz Radiation-cooled power pentode
  • RL65A – 65 W, 15 MHz Radiation-cooled power pentode
  • UA025A – 10 kV, 250 mA Argon-filled, half-wave rectifier with an E27 Edison screw lamp base and an anode screw top cap
  • UA1A – 8 kV, 1 A Half-wave Mercury-vapor rectifier with an E40 Goliath Edison screw lamp base and an anode screw top cap
  • UA3A – 11 kV, 3 A Half-wave Mercury-vapor rectifier with an E40 Goliath Edison screw lamp base and an anode screw top cap
  • UA5A – 11 kV, 5 A Half-wave Mercury-vapor rectifier with a 2-pin base and an anode screw top cap
  • ZD1000F – 60 MHz, 1 kW Radiation-cooled power triode
  • ZD1XB – 1.2 kW Forced-air cooled AF power triode
  • ZD3XH – 60 MHz, 3 kW Forced-air cooled power triode
  • ZD8XA – 20 MHz, 8 kW Forced-air cooled power triode
  • ZD12YA – 20 MHz, 12 kW Forced-air cooled AF power triode
  • ZE025XS – 400 MHz, 250 W Forced-air cooled beam power tetrode

Media related to Tesla vacuum tubes at Wikimedia Commons

Media related to Tesla gas discharge tubes at Wikimedia Commons

Tungsram systems

Signal and low-power tubes before 1934

The Tungsram system was composed of a maximum of three letters and three or four digits.[94][93] It was phased out after 1934 when Tungsram adopted the Mullard–Philips scheme, frequently preceding it with the letter T, as in TAD1 for AD1.

  • Letter(s): Function/type:
Note: A preceding letter A indicates an indirectly heated tube
  • D – Diode
  • DD – Dual diode
  • DGSpace charge grid tetrode (the 2nd grid is the control grid)
  • DS – Diode + tetrode
  • FH – Remote-cutoff hexode pentagrid converter
  • G – Preamplifier triode
  • H – Signal triode or grid-leak detector
  • HP – RF pentode
  • HR – RF triode
  • L – AF power triode
  • MH – Hexode pentagrid converter
  • MO – Octode pentagrid converter
  • P – Power triode
  • PP – Power pentode
  • PV – Full-wave rectifier
  • R – High-μ triode
  • S – Tetrode
  • V – Half-wave rectifier
  • X – US-licensed tube
  • A number:
  • Up to 2 digits: Filament/heater voltage
  • Remaining digits: Filament/heater current in tens of mA, but the last digit is sequentially assigned

Examples:[87]

  • AS4100 – Tetrode, 4 V/1 A (=100 × 10 mA) heater
  • FH4105 = E449 = RENS1234 – Remote-cutoff hexode mixer, 4 V/1.2 A heater
  • HP4101 = E446 = RENS1284 – RF pentode, 4 V/1 A filament
  • HP4106 = E447 = RENS1294 – Remote-cutoff RF pentode, 4 V/1.1 A heater
  • HR406 = A425 = RE034 – RF triode, 4 V/60 mA (=6 × 10 mA) filament
  • L414 = B409 = RE134 – Triode, 4 V/140 mA (=14 × 10 mA) filament
  • MH2018 = B2048 = RENS1824 – Hexode mixer, 20 V/180 mA (=18 × 10 mA) heater
  • MH4100 = E448 = RENS1224 – Sharp-cutoff hexode mixer, 4 V/1.2 A heater
  • PP2018D = B2043 = RENS1823D = L2318D – Power pentode, 20 V/180 mADC series heater
  • PP4101 = E443H = RES964 = L496D = RTP4 = P435 – Power pentode, 4 V heater
  • PV4200 – Full-wave rectifier, 4 V/2 A (=200 × 10 mA) filament
  • R2018 = B2038 = REN1821 = A2118 – Triode, 180 mA heater
  • S406 = A442 = RES094 – Tetrode with a screen grid, 4 V/60 mA filament
  • S2018 = B2042 = RENS1820 = H2018D – RF Tetrode, 180 mA heater
Transmitting tubes
  • Letter(s): Function/type:
  • OQ, OQQ, OT, P – Triode
  • OS – Pentode
  • A number: Anode voltage in V
  • A slash followed by a number: Anode dissipation in W

Media related to Tungsram vacuum tubes at Wikimedia Commons

Russian systems

Vacuum tubes produced in the former Soviet Union and in present-day Russia are assigned in Cyrillic. Some confusion has been created in transliterating these designations to Latin.

1929 System

The first system was introduced in 1929. It consisted of one or two cyrillic letter(s) and a sequentially assigned number with up to 3 digits[93]

  • A letter: Function/type:
  • A dash followed by a sequentially assigned number

Examples:[95][96]

  • ВО-116, ВО-188, ВО-202VO-116, VO-188, VO-202 – Full-wave rectifiers with an oxide-coated cathode
  • СБ-242, СБ-244, СО-241SB-242, SB-244, SO-241 – 2-volts directly heated tube set for budget-priced portable, battery-operated radios
  • СО-118, СО-122, СО-124SO-118 (Triode), SO-122 (Power pentode), SO-124 (Tetrode) – 4-volts indirectly heated tube set for premium radios
  • СО-148SO-148 – Remote-cutoff tetrode with an oxide-coated cathode
  • СО-242SO-242 – Heptode with an oxide-coated cathode
  • УБ-110UB-110 – Triode with a Baria-coated cathode
  • УО-104, УО-186UO-104, UO-186 – Power triodes
  • СБ-154, УБ-107, УБ-110, УБ-132SB-154, UB-107, UB-110, UB-132 – Budget-priced, 4-volts directly heated power triodes

In 1937, the Soviet Union purchased a tube assembly line from RCA (who at the time had difficulties raising funds for their basic operations), including production licenses and initial staff training, and installed it on the Светлана (Svetlana) plant in St. Petersburg, Russia. US-licensed tubes were produced since then under an adapted RETMA scheme.

Examples:[97]

  • 6А7 = 6A7Pentagrid converter
  • 6Ф5 = 6F5 – High-μ triode
  • 6Ф6 = 6F6 – Power pentode
  • 6Х6 = 6H6 – Dual diode
  • 6Ж7 = 6J7 – Sharp-cutoff pentode
  • 6Л6 = 6L6Beam power tetrode
  • 6Л7 = 6L7 – Pentagrid converter
  • 6Н7 = 6N7 – Dual power triode
  • 6АЖ5 = 6AJ5 – Low (6.3-80 V) anode voltage, sharp-cutoff pentode

The Chinese 广州曙光无线电厂 (Guangzhou Shuguang Radio Factory) did the reverse, adapting the GOST system (below) to Latin letters for some of their tubes.[98]

GOST System

In 1950, a 5-element system (Russian: Государственный Стандарт "State standard" ГОСТGOST 5461-50 and later revisions 5461-56, 5461-59, 13393-67, 13393-76) was introduced in the (then) Soviet Union for designating receiver vacuum tubes.[99][permanent dead link][100]

  • A number: Filament/heater voltage rounded to the nearest whole number; 06 means 625 mV
  • Letter(s): Function/type:
  • МНMN – Triode Mechanotron-type(ru) mechano-electronic displacement sensor[101]
  • ПP – Power pentode or beam power tetrode
  • РR – Dual tetrode or dual pentode
  • СS – Triode
  • УU – Power triode (was soon deprecated)
  • ФF – Triode + pentode
  • ХH or X – Dual diode
  • МХMH – Diode Mechanotron-type mechano-electronic displacement sensor
  • МДХMDH – Diode Mechanotron-type mechano-electronic pressure sensor
  • МУХMUH – Diode Mechanotron-type mechano-electronic rotation sensor
  • A sequentially assigned number
  • A letter: Construction type, base, envelope outline:
  • <none> – All-metal tube
  • ДDDisk-seal tube for UHF operation
  • ЖJAcorn tube
  • КK – Ceramic/metal envelope
  • ЛL – Loctal base
  • МM – Short envelope with an Octal base
  • НNNuvistor
  • ПP – All-glass Miniature 7-pin or Noval, envelope diameter 19 or 22 mm (34 or 78 in)
  • РR – Subminiature all-glass wire-ended, envelope diameter up to 5 mm (0.2 in)
  • АA – Subminiature all-glass wire-ended, envelope diameter 5 to 8 mm (0.2 to 516 in)
  • БB – Subminiature all-glass wire-ended, envelope diameter 8 to 10 mm (516 to 0.4 in)
  • ГG – Glass envelope, diameter 10 to 22 mm (0.4 to 78 in)
  • СS – Glass envelope, diameter more than 22 mm (78 in), typically with an Octal base
  • An optional dash followed by one or more letters indicating special characteristics; in most cases this means construction upgrades rather than product binning:
GOST 5461-50:
  • РR – Improved quality
  • ВРVR – Increased reliability
  • ДРDR – Very long life
  • ЕРYeR – Long-life
GOST 13393-76:
  • ВV – Ruggedized (shock/vibration-resistant)
  • ДD – Long-life (≥10000 h)
  • ЕYe – Long-life (≥5000 h)
  • ИI – Pulse-rated power tube
  • КK – Low-microphonics/low-noise

For examples see below

Professional tubes

Used for professional/industrial/computer/telecommunications tubes[102][93]

  • Letter(s): Function/type acronym
  • ВГVG – Gas-discharge or Mercury-vapor rectifier
  • ВИVI – Pulse-rated rectifier
  • ЕГ, ОГYeG, OGDekatron
  • ИIIgnitron
  • И ⟼ I – Optical indicator tube, ≥two-lettered
  • ИНIN – Neon-filled
  • ИТ ⟼ IT – Luminescent thyratron(s)
  • В ⟼ V – Traveling-wave tube (Russian: Волна "Wave"), ≥two-lettered
  • ТГ, ТГИTG, TGI – Gas-filled thyratron
  • ТРTR – Mercury-vapor thyratron
  • ТХ, ТХИ, МТХTH, THI, MTH – Noble gas-filled, cold-cathode thyratron (Russian: Холодный "Cold")
  • ФF – Phototube
  • Remaining elements:
Ignitrons, Rectifier tubes, Thyratrons:
  • A digit
  • A dash followed by a number: Anode current in A
  • A slash followed by a number: Anode voltage in kV
  • A letter: Cooling method:
  • <none> – All-glass, radiation/convection-cooled
  • АA – Water-cooled
Transmitting tubes:
  • A dash followed by a sequentially assigned number
  • A letter: Cooling method:
  • <none> – All-glass, radiation/convection-cooled
  • АA – Liquid-cooled
  • БB – Forced air-cooled
  • КK – Contact/conduction-cooled
  • ПP – Water/vapor-cooled
Phototubes and Photomultipliers:
  • A dash followed by a sequentially assigned number
  • A letter:
  • ВV – Vacuum
  • ГG – Gas-filled
  • СS – Caesium-activated Antimony cathode
  • ЦC – Caesium cathode
Radiation detectors:
  • A letter:

For examples see below

Japanese systems

1920s–40s System

  • A letter: Function/type[104]
  • Another letter: Base and envelope outline
  • F – Globe, European 4-pin A4A base
  • G, SST or Metal, Octal base
  • NAcorn tubes etc., wire-ended
  • T – ST, Large 7-pin U7B base with 0.855 in (21.7 mm) pin circle diameter
  • t – ST, Small 7-pin U7A base with 34 in (19.1 mm) pin circle diameter
  • V – 4-pin UV4 base
  • X – ST, 4-pin UX4 base
  • x – Peanut 4-pin base
  • Y – ST, 5-pin UY5 base
  • y – Peanut 5-pin base
  • Z – ST, 6-pin U6A base
  • A dash followed by a sequentially assigned number or the designation of the American original
  • An optional dash followed by a letter: Variant

Examples:[105][106]

  • EZ-6E5 = UZ-6E5 = 6E5 – Top-view, "Magic Eye"-type tuning indicator, 6.3 V/300 mA heater, U6A base
  • EZ-6G5 = EZ-6U5 = 6G5/6U5 – Top-view, vari-μ "Magic Eye"-type tuning indicator, 6.3 V/300 mA heater, U6A base
  • Kt-6H6-A – Dual diode, 6.3 V/300 mA heater, U7A base
  • KX-12-B – Half-wave rectifier 5.0 V/500 mA filament, UX4 base
  • KX-80-B – Half-wave rectifier 5.0 V/1.25 A filament, UX4 base
  • KX-202-A – Half-wave rectifier 7.5 V/1.25 A filament, UX4 base
  • KX-6901 – Half-wave rectifier 2.5 V/5 A filament, UX4 base
  • UF-101 = Grammont TM – Triode, 80-135 V anode, 4.0 V/650 mA filament, European A4A base
  • UF-101-A – UF-101 with a 350 V anode and a 5.0 V/600 mA filament
  • UF-109 – Triode, 135 V anode, 1.1 V/60 mA filament
  • UF-111 – Tetrode, 135 V anode, 1.1 V/60 mA filament
  • UF-134 = UX-34 = UX-134 = 34 = RCA-234 = CX-334 – Remote-cutoff pentode, 2 V/60 mA filament, UX4 base with control grid on top cap
  • UG-6P7-G = 6P7-G – Common cathode, triode/remote-cutoff pentode oscillator/mixer, 6.3 V/300 mA heater, Octal base
  • UN-100 – Audion triode, 2.0 V/1.0 A filament, screw/leads, Globe envelope
  • UN-109-C – Dual triode, 1.1 V/120 mA filament; two units of UX-109A
  • UN-554Acorn Sharp-cutoff VHF pentode, 5.5 V/300 mA heater
  • UN-555Acorn VHF Triode, 5.5 V/300 mA heater
  • UN-954 = 954Acorn Sharp-cutoff pentode
  • UN-955 = 955Acorn Triode
  • US-6A8 = 6A8 – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 6.3 V/800 mA heater, Octal base
  • US-6F7-A = 6F7A – Triode + pentode, 6.3 V/300 mA heater, Octal base; Metal version of 6F7
  • US-6J7 = 6J7Dual-control, sharp-cutoff RF pentode, 6.3 V/300 mA heater, Octal base with control grid on top cap
  • US-6K7 = 6K7 – Dual-control, remote-cutoff RF pentode, 6.3 V/300 mA heater, Octal base with control grid on top cap
  • US-6L7-G = 6L7-G – Mixing heptode requiring a separate oscillator, 6.3 V/300 mA heater, Octal base
  • US-6305 – VHF Pentode, 6.3 V/300 mA heater
  • Ut-6L7-G – US-6L7-G with an U7A base
  • UV-102 – Triode, 2.0 V/750 mA filament, UV4 base
  • UX-10-A – Triode, 7.5 V/1.25 A filament, UX4 base
  • UX-12-A = 12-A = UX-112-A = CX-112-A – Medium-μ triode, 5 V/250 mA filament, UX4 base
  • UX-30 – Triode, 2 V/60 mA filament, UX4 base
  • UX-31-A – Triode, 2.0 V/130 mA filament, UX4 base
  • UX-32 = 32 = RCA-232 = CX-332 – Sharp-cutoff tetrode, 2 V/60 mA filament, UX4 base with control grid on top cap
  • UX-47-A (2.5 V/1.75 A filament), UX-47-C (5.0 V/500 mA filament) – Power pentode, UX4 base; similar to 47
  • UX-71-A = 71-A = UX-171-A = CX-371-A – Power triode, 5 V/250 mA filament, UX4 base
  • UX-99 = X99 = UX-199 – Low-μ triode, 3.3 V/60 mA filament, UX4 base
  • UX-109 (1.3 V/80 mA filament), UX-109-A (1.1 V/60 mA filament) – Triode, UX4 base
  • UX-110 – Power triode, 1.3 V/160 mA filament, UX4 base
  • UX-111, UX-111-B – Space charge grid tetrode, 1.3 V/80 mA filament, UX4 base
  • UX-167 – Sharp-cutoff RF pentode, 2 V/60 mA filament, UX4 base
  • UX-201-A = 01-A – General-purpose low-μ triode, 5 V/250 mA filament, UX4 base
  • UX-202-A – Power triode, 7.5 V/1.25 A filament, UX4 base
  • UX-226 = 26 = CX-326, UX-26-B – Medium-μ RF triode, 1.5 V/1.05 A filament, UX4 base
  • UX-6202 – RF Tetrode, 1.9 V/50 mA filament, UX4 base
  • UY-6A3-B – Power triode, 6.3 V/1.6 A heater, UY5 base; indirectly heated variant of 2A3
  • UY-10-H – Triode, 6.3 V/800 mA heater, UY5 base
  • UY-11-A – Pentode, 1.1 V/60 mA filament, UY5 base
  • UY-36-A – RF Tetrode, 6.3 V/300 mA heater, UY5 base
  • UY-37-A – Triode, 6.3 V/300 mA heater, UY5 base
  • UY-38-A – Power pentode, 6.3 V/300 mA heater, UY5 base
  • UY-39-A – RF Pentode, 6.3 V/300 mA heater, UY5 base
  • UY-45-H – Power triode, 6.3 V/800 mA heater, UY5 base; indirectly heated variant of 45
  • UY-46-C – Class-B tetrode, 2.5 V/500 mA filament, UY5 base
  • UY-47 = 47 = RCA-247 = C-347, UY-47-A (2.5 V/1.75 A filament), UY-47-B (2.5 V/500 mA filament) – 2.7 W Power pentode, UY5 base; 46 with a suppresser grid connected to a filament center-tap
  • UY-56-A – Triode, 2.5 V/800 mA heater, UY5 base
  • UY-57-S – Pentode, 2.5 V/1.0 A heater, UY5 base
  • UY-76-A – Triode, 6.3 V/300 mA heater, UY5 base
  • UY-133 (1.1 V/125 mA filament), UY-133-A (1.1 V/60 mA filament) – Power pentode, UY5 base
  • UY-169 – Power pentode, 2 V/120 mA filament, UY5 base
  • UY-224 = 24 = C-324, UY-224-A = 24-A = C-324A, UY-24-B – Sharp-cutoff tetrode, 2.5 V/1.75 A heater, UY5 base with control grid on top cap
  • UY-227 = 27 = C-327 (2.5 V/1.75 A heater), UY-27-A (2.5 V/1.5 A heater), UY-27-B (2.5 V/1.0 A heater) – Medium-μ triode, UY5 base
  • UY-233 = 33 = RCA-233 = C-333 – Power pentode, 2 V/260 mA filament, UY5 base
  • UY-235 = 35/51 = C-335, UY-35-B – Remote-cutoff RF tetrode, 2.5 V/1.75 A heater, UY5 base; variant of the UY-224-A tetrode
  • UY-247 = 47 = RCA-247 = C-347 – Power pentode, 2.5 V/1.75 A filament, UY5 base
  • UY-536 – Tetrode, 6.3 V/300 mA heater, UY5 base
  • UY-537 – Triode, 6.3 V/300 mA heater, UY5 base
  • UY-538 – Power pentode, 6.3 V/300 mA heater, UY5 base
  • UY-539 – RF Pentode, 6.3 V/300 mA heater, UY5 base
  • UY-807 = 807, UY-807-A (6.3 V/900 mA heater), UY-807-B (12.0 V/450 mA heater) – Transmitting beam power tetrode, UY5 base
  • UY-6301 – Triode, 6.3 V/600 mA heater, UY5 base
  • Uy-11-M – Tetrode, 1.1 V/60 mA filament, Peanut 5-pin base
  • Uy-14-M – RF Pentode, 1.1 V/60 mA filament, Peanut 5-pin base
  • UZ-12-C – Dual triode, 5.0 V/500 mA filament, U6A base; dual unit of 12A
  • UZ-30-C, UZ-30-MC – Dual triode, 2.0 V/120 mA filament, U6A base; dual unit of 30
  • UZ-31-MC – Dual power triode, 2.0 V/260 mA filament, U6A base; dual unit of 31
  • UZ-33-A – Dual triode, 2.0 V/260 mA filament, U6A base; dual unit of 33
  • UZ-42 = 42 – Power pentode, U6A base; 2A5 with a 6.3 V/700 mA heater
  • UZ-47-D (5.0 V/500 mA filament), UZ-47-G (5.0 V/250 mA filament), UZ-47-H (5.0 V/1.65 A filament), UZ-47-K (5.0 V/500 mA filament) – Modulator power pentode, U6A base
  • UZ-55 = 55 – Dual diode + medium-μ triode, 2.5 V/1 A heater, U6A base
  • UZ-57 = 57, UZ-57-A – Sharp-cutoff pentode, 2.5 V/800 mA heater, U6A base
  • UZ-58 = 58, UZ-58-A – Remote-cutoff RF/IF pentode, 2.5 V/1 A heater, U6A base
  • UZ-75 = 75 – 6H6-type Dual diode + 6F5-type high-μ triode, 6.3 V/300 mA heater, U6A base
  • UZ-77 = 77 – Sharp-cutoff pentode, 6.3 V/300 mA heater, U6A base
  • UZ-78 = 78 – Remote-cutoff pentode, 6.3 V/300 mA heater, U6A base
  • UZ-79 = 79 – Dual power triode, 6.3 V/600 mA heater, U6A base
  • UZ-89 = 89 – 3.4 W Power pentode, 6.3 V/400 mA heater, U6A base
  • UZ-109 – Dual triode, 1.1 V/100 mA filament, U6A base
  • UZ-130-C – Dual triode, 1.1 V/240 mA filament, U6A base
  • UZ-133-D – Triode + pentode, 1.1 V/125 mA filament, U6A base
  • UZ-135 – Heptode pentagrid converter, 1.1 V/130 mA filament , U6A base
  • UZ-1C6-B (1C6) – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 2.0 V/120 mA filament, U6A base
  • UZ-2A5 = 2A5 – Power pentode, 2.5 V/1.75 A heater, U6A base
  • UZ-2A6 = 2A6 – Dual diode + high-μ triode, 2.5 V/800 mA heater, U6A base with control grid on top cap
  • UZ-6C6 = 6C6 – Dual-control, sharp-cutoff RF pentode, 6.3 V/300 mA heater, U6A base with control grid on top cap
  • UZ-6D6 = 6D6 – Dual-control, remote-cutoff RF pentode, 6.3 V/300 mA heater, U6A base with control grid on top cap
  • UZ-6E5 – See EZ-6E5
  • UZ-6L6-A (6L6-G) – Beam power tetrode, 6.3 V/900 mA heater, U6A base
  • UZ-6001 – Pentode, 6.3 V/300 mA heater, U6A base
  • UZ-6302 – Video pentode, 6.3 V/600 mA heater, U6A base
  • UZ-6304 – Power pentode, 6.3 V/700 mA heater, U6A base

JIS C 7001 System

JIS C 7001 was published in 1951 and revised in 1965 and 1970[104]

  • A number: Filament/heater voltage category, as in the RETMA scheme
  • 1 – 1...1.9 V
  • 2 – 2...2.4 V
  • 3 – 2.5...3.9 V
  • 4 – 4...4.9 V
  • 5 – 5...5.9 V
  • 6 – 6...6.9 V, etc.
  • A letter: Base and envelope outline
  • A, B – Special base
  • CCompactron, Duodecar base
  • D – Subminiature round (=circular) base
  • E – Subminiature flat (=inline) base
  • FST, European 4-pin A4A base
  • G – GT, Octal base
  • H – All-glass miniature, Magnoval base
  • K – Ceramic
  • L – Loctal base
  • M – All-glass miniature, Miniature 7-pin base
  • NNuvistor
  • QAcorn tube
  • R – All-glass miniature, Noval or Neonoval base
  • T – ST, Large 7-pin U7B base
  • W – ST, Small 7-pin U7A base
  • X – ST, 4-pin UX4 base
  • Y – ST, 5-pin UY5 base
  • Z – ST, 6-pin U6A base
  • A dash followed by up to three letters: Structure and usage
—Even number after K: Full-wave rectifier
—Odd number after K: Half-wave rectifier
  • L – Low-μ triode (μ<30)
  • P – Power tetrode or pentode
  • R – Sharp-cutoff tetrode or pentode
  • SSpace charge grid tetrode (the 2nd grid is the control grid)
  • TThyratron
  • V – Remote-cutoff tetrode and pentode
  • X – Other
  • A sequentially assigned number
  • An optional letter: Variant

Examples:[105][106]

  • 1D-E14 – Subminiature bar-type tuning indicator, 1.4 V/200 mA filament
  • 1D-K25 – 6.5 kVPIV Subminiature rectifier, 0.6 V/200 mA filament
  • 1D-K27 – 10 kVPIV Subminiature rectifier, 0.7 V/200 mA filament
  • 1D-K29 – 9 kVPIV Subminiature rectifier, 900 mV/200 mA filament
  • 1E-DR1 – Subminiature diode + pentode, 1.25 V/25 mA filament
  • 1E-R11 – Subminiature RF pentode, 1.25 V/25 mA filament
  • 1E-R20 – Subminiature pentode, 1.25 V/10 mA filament
  • 1R-K23 = 1S2A/DY87 – 27 kVPIV CRT EHT Rectifier, 1.4 V/550 mA heater, Noval base, silicone-coated envelope to prevent flush-over in high-humidity and low atmospheric-pressure conditions
  • 1R-K31 – 22 kVPIV CRT EHT Rectifier, 1.25 V/500 mA filament, Noval base
  • 2D-H6 – Subminiature VHF triode, 2.3 V/600 mA heater
  • 2N-H12Nuvistor triode
  • 2X-L2A – Low-μ triode, UX4 base
  • 3D-HH12 – 6D-HH12 Dual RF triode with a different heater
  • 3D-HH13 – 6D-HH13 Dual RF triode with a different heater
  • 3M-P26 – Power pentode, Miniature 7-pin base; 4M-P26 with a 3.5 V/600 mA heater
  • 3M-R24 – Semiremote-cutoff RF pentode, 3.15 V/600 mA heater, Miniature 7-pin base
  • 3M-R28 – RF pentode, 3.15 V/300 mA heater, Miniature 7-pin base
  • 3M-V7 – Semiremote-cutoff RF pentode, 3.15 V/600 mA heater, Miniature 7-pin base
  • 3W-C5 – 6W-C5 Heptode pentagrid converter with a 2.5 V/1.0 A heater
  • 3Z-P1 – 6Z-P1 Power pentode with a 2.5 V/900 mA heater
  • 3Z-DH3, 3Z-DH3A – 6Z-DH3, 6Z-DH3A Diode + triode with a 2.5 V/1.0 A heater
  • 4D-H6 – 6D-H6 RF Triode with a 4.3 V/300 mA heater
  • 4D-HH13 – 3D-HH13, 6D-HH13 Dual triode with a 4.6 V/450 mA heater
  • 4M-P12 – 6M-P12, 8M-P12, 9M-P12 AF Power pentode with a 4.7 V/600 mA heater
  • 4M-P26 – 3M-P26 Power pentode with a 4.5 V/450 mA heater
  • 4R-HH2 – 6R-HH2, 17R-HH2 Dual VHF triode with a 4.2 V/600 mA heater
  • 4R-HH6 – Dual triode, 4.2 V/600 mA heater, Noval base
  • 4R-HH8 = 4KN8 – 6R-HH8 Dual VHF triode with a 4.2 V/600 mA heater
  • 4R-HH9 – 6R-HH9 Dual RF triode with a 4.2 V/600 mA heater
  • 4R-HH15 – 6R-HH15 Dual RF triode with a 4.2 V/600 mA heater
  • 5G-K3 – 1 kVPIV Half-wave rectifier, 5.0 V/700 mA heater, Octal base
  • 5G-K4 = 5CG4 – 1.4 kVPIV Half-wave rectifier 5.0 V/2.0 A heater, Octal base
  • 5G-K18 – 1.55 kVPIV Full-wave rectifier, 5.0 V/3.0 A filament, Octal base
  • 5G-K20 – 1 kVPIV Full-wave rectifier 5.0 V/1.9 A heater, Octal base
  • 5G-K22 – 1.55 kVPIV Full-wave rectifier 5.0 V/3.0 A heater, Octal base
  • 5G-K24 – 1.5 kVPIV Full-wave rectifier 5.0 V/1.9 A heater, Octal base
  • 5M-HH3 – 6M-HH3, 9M-HH3 Dual VHF triode with a 4.7 V/600 mA heater
  • 5M-K9 – 1 kVPIV, 60 mA Half-wave rectifier, 5.0 V/600 mA heater, Miniature 7-pin base
  • 5R-K16 – 1 kV, 2×75 mA Full-wave rectifier, 5 V/1.2 A heater, Noval base
  • 5M-L8 – UHF Oscillator triode, 4.7 V/300 mA heater, Miniature 7-pin base; similar to 6DZ4
  • 5R-DDH1 – Dual diode + triode, 4.7 V/600 mA heater, Noval base
  • 5R-HR1 – Triode + pentode, 5.3 V/600 mA heater, Noval base
  • 5R-K16 – 1 kVPIV Full-wave rectifier, 5.0 V/1.2 A heater, Noval base
  • 6B-B14 – Beam power tetrode used as CRT horizontal deflection amplifier, 6.3 V/600 mA heater, Magnoval base
  • 6B-B15 – Beam power tetrode used as CRT horizontal deflection amplifier, 6.3 V/1.2 A heater
  • 6C-A10 – 30 W Compactron AF Power triode, 6.3 V/1.5 A heater
  • 6D-H6 – Subminiature RF triode; 4D-H6 with a 6.3 V/200 mA heater
  • 6D-H8, 6D-H9 – Subminiature triodes, 6.3 V/150 mA heater
  • 6D-HH12 – Subminiature dual RF triode with a base anticipating the Nuvistor; 3D-HH12 with a 6.3 V/300 mA heater
  • 6D-HH13 – Subminiature dual triode with a base anticipating the Nuvistor used as cascode; 3D-HH13, 4D-HH13 with a 6.3 V/300 mA heater
  • 6G-A4 – Power triode, 6.3 V/750 mA heater, Octal base
  • 6G-B3A – 13 W Beam power tetrode used as CRT horizontal deflection amplifier, Octal base; 12G-B3A, 17G-B3A with a 6.3 V/1.2 A heater
  • 6G-B6 – Beam power tetrode used as CRT horizontal deflection amplifier, Octal base; 12G-B6, 25G-B6 with a 6.3 V/1.2 A heater
  • 6G-B7 – 15 W Beam power tetrode used as CRT horizontal deflection amplifier, Octal base; 12G-B7 with a 6.3 V/1.2 A heater
  • 6G-B8 – Beam power tetrode, 6.3 V/1.5 A heater, Octal base
  • 6G-B9 – Beam power tetrode used as CRT horizontal deflection amplifier, 6.3 V/1.2 A heater, Octal base
  • 6G-B13 – Beam power tetrode, Octal base; 50G-B13 with a 6.3 V/1.2 A heater
  • 6G-C5 – Heptode pentagrid converter, 6.3 V/300 mA heater, Octal base; similar to 6SA7-GT
  • 6G-DE2 – Diode + tuning indicator, 6.3 V/300 mA heater, Octal base
  • 6G-E7 = 6DL7 – Sharp + remote-cutoff tuning indicator, 6.3 V/300 mA heater, Octal base
  • 6G-E12A – 2-channel "Magic Eye"-type tuning indicator, rectangular target, 6.3 V/300 mA heater, Octal base
  • 6G-H4 – CRT EHV Shunt regulator power triode, 6.3 V/200 mA heater, Octal base, considerable X-radiation
  • 6G-H7 – CRT EHV Shunt regulator power triode, 6.3 V/200 mA heater, Octal base, considerable X-radiation
  • 6G-K17 – CRT horizontal deflection output booster/damper/efficiency diode, Octal base; 12G-K17 with a 6.3 V/1.3 A heater
  • 6G-R7 – Semiremote-cutoff pentode, 6.3 V/300 mA heater, Octal base
  • 6H-B26 – 18 W AF Beam power tetrode, 6.3 V/1.25 A heater, Magnoval base
  • 6M-DE1 – Diode + "Magic Eye"-type tuning indicator, 6.3 V/150 mA heater, Miniature 7-pin base
  • 6M-E2 – Tuning indicator, 6.3 V/300 mA heater, Miniature 7-pin base
  • 6M-E4 – "Magic Finger"-type tuning indicator, 6.3 V/200 mA heater, Miniature 7-pin base
  • 6M-E5 = 6E5-M – "Magic Eye"-type tuning indicator, 6.3 V/150 mA heater, Miniature 7-pin base; similar to 6E5-M
  • 6M-E10 – "Magic Eye"-type tuning indicator, 6.3 V/150 mA heater, Miniature 7-pin base
  • 6M-H1 – VHF Triode, 6.3 V/400 mA heater, Miniature 7-pin base
  • 6M-HH3 – Dual VHF triode used as oscillator/mixer in analog TV receivers, Miniature 7-pin base; 5/9M-HH3 with a 6.3 V/450 mA heater
  • 6M-L2 – VHF Triode, 6.3 V/175 mA heater, Miniature 7-pin base
  • 6M-L3 – UHF Triode, 6.3 V/175 mA heater, Miniature 7-pin base
  • 6M-P12 – Power pentode, Miniature 7-pin base; 4M-P12, 8M-P12, 9M-P12 with a 6.3 V/450 mA heater
  • 6M-P17 – Power pentode, 6.3 V/500 mA heater, Miniature 7-pin base
  • 6M-P20 – Power pentode, 6.3 V/600 mA heater, Miniature 7-pin base
  • 6M-R25 – Pentode, Miniature 7-pin base; 12M-R25 with a 6.3 V/300 mA heater
  • 6M-R26 – AF Pentode, Miniature 7-pin base; 12M-R26 with a 6.3 V/300 mA heater
  • 6N-H10Nuvistor UHF Triode, 6.3 V/120 mA heater
  • 6R-A2 – Power triode now used as output transformerless audio amplifiers in audiophile gear, 6.3 V/760 mA heater, Noval base
  • 6R-A3 – Power triode used as series-pass regulator in stabilized DC power supplies, 6.3 V/1.0 A heater, Noval base
  • 6R-A5 – Power triode used as series-pass regulator in stabilized DC power supplies, 6.3 V/1.0 A heater, Noval base
  • 6R-A6 – Power triode used as CRT vertical deflection amplifier, 6.3 V/900 mA heater, Noval base
  • 6R-A8 – AF Power triode, 6.3 V/1.0 A heater, Noval base
  • 6R-A9 – Power triode used as CRT vertical deflection amplifier, 6.3 V/600 mA heater, Noval base
  • 6R-AL1 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 6.3 V/860 mA heater, Noval base
  • 6R-AL2 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 6.3 V/900 mA heater, Noval base
  • 6R-B10 – Beam power tetrode, 6.3 V/1.0 A heater, Noval base
  • 6R-B11 – Beam power tetrode used as CRT vertical deflection amplifier, Noval base; 8R-B11 with a 6.3 V/800 mA heater
  • 6R-B12 – Beam power tetrode used as CRT horizontal deflection amplifier, Noval base; 12R-B12 with a 6.3 V/600 mA heater
  • 6R-DDP1 – Dual diode + power pentode, 6.3 V/750 mA heater, Noval base
  • 6R-DHV1 – Diode + triode + remote-cutoff pentode, Noval base; 20R-DHV1 with a 6.3 V/480 mA heater
  • 6R-DHV2 – Diode + triode + remote-cutoff pentode, 6.3 V/500 mA heater, Noval base
  • 6R-E13 – Side-view, band-type tuning/level indicator, 6.3 V/200 mA heater, Noval base
  • 6R-EE1 – Dual tuning indicator, 6.3 V/200 mA heater, Noval base
  • 6R-H2 – Triode used in grounded-grid amplifiers, 6.3 V/300 mA heater, Noval base
  • 6R-HH1 – Dual triode used in a cascode, 6.3 V/400 mA heater, Noval base
  • 6R-HH2 – Dual VHF triode used in a cascode, 6.3 V/400 mA heater, Noval base; 4/17R-HH2 with a 6.3 V/400 mA heater
  • 6R-HH8 = 6KN8 – Dual semiremote-cutoff VHF triode used in a cascode, Noval base; 4R-HH8 with a 6.3 V/400 mA heater
  • 6R-HH9 – Dual RF triode, Noval base; 4R-HH9 with a 6.3 V/400 mA heater
  • 6R-HH15 – Dual RF triode, Noval base; 4R-HH15 with a 6.3 V/300 mA heater
  • 6R-HP2 – Triode + pentode, Noval base; 8R-HP2, 32R-HP2 with a 6.3 V/780 mA heater
  • 6R-HP3 – Triode + pentode, Noval base; 8R-HP3, 10R-HP3 with a 6.3 V/750 mA heater
  • 6R-HV1 – Triode + remote-cutoff pentode, 6.3 V/500 mA heater, Noval base
  • 6R-K19 = 6BR3 – CRT horizontal deflection output booster/damper/efficiency diode, Noval base; 12R-K19 with a 6.3 V/1.2 A heater
  • 6R-P10 – Power pentode, 6.3 V/500 mA heater, Noval base
  • 6R-P15 – Power pentode, 6.3 V/750 mA heater, Noval base
  • 6R-P22 – Power pentode, 6.3 V/600 mA heater, Noval base
  • 6R-R8, 6R-R8C – Wide-band pentode, 6.3 V/300 mA heater, Noval base
  • 6R-R21 – Wide-band tetrode, 6.3 V/300 mA heater, Noval base
  • 6W-C5 – Heptode pentagrid converter; 12W-C5 with a 6.3 V/300 mA heater, U7A base
  • 6Z-1V, 6Z-3V, 6Z-AM1 – Pentodes, 6.3 V/300 mA heater, U6A base; similar to 6C6
  • 6Z-DH3, 6Z-DH3A – Diode + triode, 6.3 V/300 mA heater, U6A base
  • 6Z-E1 – Tuning indicator, 6.3 V/300 mA heater, U6A base; similar to 6E5
  • 6Z-E3 – Tuning indicator, 6.3 V/300 mA heater, U6A base; similar to 6E5
  • 6Z-E11 – Tuning indicator, 6.3 V/150 mA heater, U6A base
  • 6Z-P1 – Power pentode, 6.3 V/300 mA heater, U6A base
  • 7M-P18, 7M-P18A – Power pentode, 7.5 V/600 mA heater, Miniature 7-pin base
  • 7M-R29 – RF Pentode, 6.75 V/140 mA heater, Miniature 7-pin base
  • 7N-R30Nuvistor Tetrode, 6.75 V/140 mA heater
  • 7R-P22 – 9R-P22 Color signal recovery pentode with a 6.7 V/600 mA heater
  • 8M-B20 – Beam power tetrode used as CRT vertical deflection amplifier, 8.0 V/600 mA heater, Miniature 7-pin base
  • 8M-P12 – 6M-P12, 9M-P12 Power pentode with a 8.5 V/300 mA heater
  • 8R-A7 – Power triode used as CRT vertical deflection amplifier, 8.0 V/600 mA heater, Noval base
  • 8R-B11 – 6R-B11 Beam power tetrode used as CRT vertical deflection amplifier, 8.5 V/600 mA heater
  • 8R-HP3 – 6R-HP3, 10R-HP3 Sync sep triode + pentode with a 8.0 V/600 mA heater
  • 8R-LP1 – Triode + pentode used as CRT vertical deflection oscillator+amplifier, 8.0 V/600 mA heater, Noval base
  • 9M-HH3 – 5M-HH3, 6M-HH3 Dual VHF triode with a 9.5 V/300 mA heater
  • 9M-P12 – 4M-P12, 6M-P12, 8M-P12 Power pentode with a 9.4 V/300 mA heater
  • 9R-A6 – 6R-A6 Power triode with a 9.5 V/600 mA heater
  • 9R-AL1 – 6R-AL1 Dual triode with a 9.0 V/600 mA heater
  • 9R-P22 – 7R-P22 Pentode used as chroma signal demodulator matrix, 9.0 V/450 mA heater
  • 10R-AL2 – 6R-AL2 Dual triode with a 9.7 V/600 mA heater
  • 10R-HP3 – 6R-HP3, 8R-HP3 Sync sep triode + pentode with a 10.5 V/450 mA heater
  • 11C-HHP1Compactron Dual triode + pentode, 11.0 V/600 mA heater
  • 12B-B14 – 6B-B14, 17B-B14, 25B-B14 Beam power tetrode used as CRT horizontal deflection amplifier with a 12.6 V/600 mA heater
  • 12G-B3, 12G-B3A – Beam power tetrode used as CRT horizontal deflection amplifier, 12.6 V/600 mA heater, Octal base
  • 12G-B3A – 6G-B3A, 17G-B3A Beam power tetrode used as CRT horizontal deflection amplifier with a 12.6 V/600 mA heater
  • 12G-B6 – 6G-B6, 25G-B6 Beam power tetrode used as CRT horizontal deflection amplifier with a 12.6 V/600 mA heater
  • 12G-B7 – 6G-B7 Beam power tetrode used as CRT horizontal deflection amplifier with a 12.6 V/600 mA heater
  • 12G-C4 – Triode/hexode mixer, 12.6 V/300 mA heater
  • 12G-C5 – Heptode pentagrid converter, 12.0 V/175 mA, Octal base; similar to 12SA7-GT
  • 12G-DH3 – Dual diode + triode, 12.0 V/175 mA heater, Octal base; similar to 6Z-DH3/A
  • 12G-DH4 – Dual diode + triode, 12.6 V/200 mA heater, Octal base
  • 12G-K10 – Full-wave rectifier, 12.6 V/300 mA heater, Octal base
  • 12G-K17 – 6G-K17 CRT horizontal deflection output booster/damper/efficiency diode with a 12.6 V/600 mA heater
  • 12G-P7 – Power pentode, 12.6 V/300 mA heater, Octal base
  • 12G-R4 – Pentode, 12.6 V/200 mA heater, Octal base
  • 12G-R6 – Pentode, 12.0 V/175 mA heater, Octal base
  • 12G-V3 – Remote-cutoff RF pentode, 12.6 V/200 mA heater, Octal base
  • 12M-R25 – 6M-R25 AF pentode with a 12.6 V/150 mA heater
  • 12M-R26 – 6M-R26 AF pentode with a 12.6 V/150 mA heater
  • 12R-B12 – 6R-B12 Beam power tetrode used as CRT horizontal deflection amplifier with a 12.6 V/300 mA heater
  • 12R-K19 = 12BR3 – 6R-K19 CRT horizontal deflection output booster/damper/efficiency diode with a 12.6 V/600 mA heater
  • 12R-K21 – CRT horizontal deflection output booster/damper/efficiency diode, 12.6 V/300 mA heater, Noval base
  • 12R-LL3 – Dual triode, center-tapped 6.3 V/450 mA resp. 12.6 V/225 mA heater, Noval base
  • 12W-C1 – Heptode pentagrid converter, 12.0 V/150 mA heater, U7A base
  • 12W-C5 – 6W-C5 Heptode pentagrid converter with a 12.0 V/175 mA heater
  • 12X-K1 – Half-wave rectifier, 12.0 V/150 mA heater, UX4 base, UY5 base
  • 12Y-L1 – Triode, 12.0 V/150 mA heater, UY5 base
  • 12Y-R1 – Pentode, 12.0 V/150 mA heater, UY5 base
  • 12Y-V1 – Remote-cutoff RF pentode, 12.0 V/150 mA heater, UY5 base
  • 12Y-V1A – Remote-cutoff RF pentode, 12.0 V/175 mA heater, UY5 base
  • 12Z-DH1 – Dual diode + triode, 12.0 V/150 mA heater, U6A base
  • 12Z-DH3A – Diode + triode, 12.0 V/175 mA heater, U6A base
  • 12Z-E6 – Tuning indicator, 12.6 V/150 mA heater, U6A base
  • 12Z-E8, 12Z-E9 – Tuning indicators, 12.6 V/150 mA heater, U6A base
  • 12Z-P1 – 6Z-P1 Power pentode with a 12.0 V/150 mA heater
  • 12Z-P1A – 6Z-P1 Power pentode with a 12.0 V/175 mA heater
  • 15M-P19 – Power pentode, 15.0 V/300 mA heater, Miniature 7-pin base
  • 16G-B16 – Beam power tetrode used as CRT horizontal deflection amplifier, 16.0 V/600 mA heater, Octal base
  • 17G-B3 – 6G-B3, 12G-B3 Beam power tetrode used as CRT horizontal deflection amplifier with a 16.8 V/450 mA heater
  • 17R-HH2 – Dual VHF triode used in cascode amplifiers, 17.0 V/150 mA heater, Noval base
  • 17R-K19 = 17BR3 – CRT horizontal deflection output booster/damper/efficiency diode, Noval base
  • 19M-R10 – Pentode, 19.0 V/100 mA heater, Miniature 7-pin base
  • 19R-LL1 – Dual triode, 19.0 V/150 mA heater, Noval base
  • 19R-P11 – Power pentode, 19.0 V/200 mA heater, Noval base
  • 20G-B19 – Beam power tetrode used as CRT horizontal deflection amplifier, 20.0 V/300 mA heater, Octal base; similar to 6BQ6-GTB
  • 20R-DHV1 – 6R-DHV1 Diode + triode + remote-cutoff pentode with a 20.0 V/150 mA heater
  • 24Z-K2 – Dual rectifier with separate cathodes used as voltage doubler, 24.0 V/150 mA heater, U6A base
  • 25B-B14 – 6B-B14, 12B-B14, 17B-B14 Beam power tetrode used as CRT horizontal deflection amplifier with a 25.0 V/300 mA heater
  • 25G-B6 – 6B-B6, 12B-B6 Beam power tetrode used as CRT horizontal deflection amplifier with a 25.0 V/300 mA heater
  • 25M-K15 – Half-wave rectifier, 25.0 V/150 mA heater, Miniature 7-pin base
  • 25M-P20 – Power pentode, 25.0 V/150 mA heater, Miniature 7-pin base
  • 25R-K19 = 25BR3 – CRT horizontal deflection output booster/damper/efficiency diode, Noval base
  • 28R-HV2 – Triode + semiremote-cutoff pentode, 28.0 V/100 mA heater, Noval base
  • 30G-K5 – 570 VPIV Half-wave rectifier, 30.0 V/175 mA heater, Octal base
  • 30G-P9 – Power pentode, 30.0 V/175 mA heater, Octal base
  • 30M-P23 – Power pentode, 30.0 V/150 mA heater, Miniature 7-pin base
  • 30M-P27 – Power pentode, 30.0 V/150 mA heater, Miniature 7-pin base
  • 32R-HP2 – 6P-HP2, 8P-HP2 Triode + pentode with a 32.0 V/150 mA heater, Noval base
  • 35M-P14 – Power pentode, 35.0 V/150 mA heater, Miniature 7-pin base
  • 36Z-K12 – Dual rectifier used as voltage doubler, 36.0 V/175 mA heater, U6A base
  • 45M-P21 – Power pentode, 45.0 V/100 mA heater, Miniature 7-pin base
  • 50C-A10 – 30 W Compactron AF Power triode, 50 V/175 mA heater
  • 50H-B26 – 18 W AF Beam power tetrode, 50 V/150 mA heater, Magnoval base
  • 50R-P25 – Power pentode, 50.0 V/150 mA heater, Noval base
  • 50R-P28 – Power pentode, 50.0 V/150 mA heater, Noval base

Professional tubes

This is very similar to the RMA system[107][108]

  • A number:
Normal tubes: Power class
Microwave tubes: Frequency in GHz
  • Letter(s): Function/type:
    Note: Dual-system tubes are assigned one letter corresponding to one system
  • A sequentially assigned number

Examples:[109][110]

  • 1G32P, 1G35P = 4C35, 1G45P = 3C45 – Hydrogen thyratrons
  • 1G50 = 2050 – Xenon thyratron
  • 1H16 = 816 – Mercury-vapor rectifier
  • 1K14Instrumentation rectifier diode
  • 1K20 = 8020 – Thermally-limited emission rectifier
  • 1K22 = 2X2A – EHT rectifier
  • 1K24 = 3B24-W – EHT rectifier
  • 1Q18, 1Q19, 1Q20, 1Q21 – Electrometer tubes
  • 1W80 – UHF power traveling-wave tube
  • 2B29 = 829B – 40 W, 200 MHz Dual beam power tetrode
  • 2B32 = 832A – 15 W, 150 MHz Dual beam power tetrode
  • 2B33 – 25 W, 60 MHz Beam power tetrode, 6.3 V/900 mA heater, UY5 base
  • 2B46 = 6146 – 120 W, 60 MHz Beam power pentode
  • 2B52 = 6252 – 2×10 W, 200 MHz Dual power tetrode
  • 2B94 = 5894 – 2×20 W, 250 MHz Dual beam power tetrode
  • 2G22P = 5C22 – Hydrogen thyratron
  • 2H28 = 3B28 – Xenon-filled half-wave rectifier
  • 2H66 = 866A – Mercury-vapor rectifier
  • 2M21, 2M51, 2M53, 2M66, 2M69, 2M892.45 GHz Magnetrons used in domestic microwave ovens
  • 2P22 = 2E22 – 30 W RF Power pentode
  • 2T11 – 20 W, 30 MHz High-μ power triode
  • 2T24 – 25 W, 60 MHz High-μ power triode
  • 2T27, 2T27A – 40 W, 100 MHz High-μ power triode
  • 3G22 = 3D22A – Gas-filled tetrode thyratron
  • 3G49P = 5949 – Hydrogen thyratron
  • 3T12 – 90 W, 75 MHz High-μ power triode
  • 3T35, 3T35A, 3T35C – 50 W, 100 MHz High-μ power triode
  • 4B13 = 813 – 100 W, 30 MHz Beam power tetrode
  • 4B38 – 150 W, 10 MHz Beam power tetrode, 6.3 V/4.8 A heater, UY5 base
  • 4F15R = 4X150A/7034 – 150 W, 150 MHz Beam power tetrode
  • 4F16R = 6816 – 115 W, 400 MHz beam power tetrode
  • 4F20R = 4X150D/7035 – 4F16R with a 26.5-volts heater
  • 4F21 = 4-125A/6155/4D21 – 125 W, 120 MHz Beam power tetrode
  • 4G48P = 5948 – Hydrogen thyratron
  • 4G63 = 5563, 4G63A = 5563A – Mercury-vapor thyratron
  • 4H32 = 4B32 – Xenon-filled half-wave rectifier
  • 4H72 = 872A – Mercury-vapor rectifier
  • 4H73 = 673 – Mercury-vapor rectifier
  • 4P55 – 120 W, 25 MHz Power pentode, 6.3 V/2.6 A heater, UY5 base
  • 4T16 = 100TL – 100 W, 40 MHz Low-μ power triode
  • 4T17 = 100TH – 100 W, 40 MHz High-μ power triode
  • 5F20RA = 4CX250B/7203 – 250 W, 500 MHz Beam power tetrode
  • 5F22 = 4-250A/6156/5D22 – 250 W, 110 MHz Beam power tetrode
  • 5F23 = 4-400A/8438 – 400 W, 110 MHz Beam power tetrode
  • 5F60R – 450 W, 500 MHz Coaxial power tetrode, 6.0 V/5.5 A heater
  • 5G44 = 5544 – Gas-filled triode thyratron
  • 5T20 = 250TL – 250 W, 40 MHz Low-μ power triode
  • 5T21 = 250TH – 250 W, 40 MHz High-μ power triode
  • 5T30 = 450TL – 450 W, 40 MHz Low-μ power triode
  • 5T31 = 450TH – 450 W, 40 MHz High-μ power triode
  • 6AV60 – 3 kW, 6.325-6.425 GHz, 4-cavity Klystron
  • 6G45 = 5545, 6G45A – Gas-filled triode thyratron
  • 6G67 = 6807 – Gas-filled triode thyratron
  • 6G68 = 6808 – Gas-filled triode thyratron
  • 6T35 = 750TL – 750 W, 40 MHz Low-μ power triode
  • 7F64R – 4 kW, 250 MHz Coaxial power tetrode, 6.0 V/68 A heater
  • 7F71RA – 3.5 kW, 250 MHz Coaxial power tetrode, 4.0 V/78 A filament
  • 7T40 = 1000T – 1 kW, 40 MHz High-μ power triode
  • 8F76R – 15 kW, 250 MHz Coaxial power tetrode, 7.5 V/120 A filament
  • 8T33 (Water-cooled), 8T39 (Water/vapor-cooled) – 10 kW, 250 MHz Power triode, 7.5 V/60 A filament
  • 9T40 – 150 kW, 2 MHz Water/vapor-cooled power triode, 18 V/315 A filament

Military naming systems

British CV and M8000s naming systems

This system prefixes a three- or four-digit number with the letters "CV", meaning "common valve" (common to all three armed services), later "civilian valve".[111] It was introduced during the Second World War to rationalise the previous nomenclatures maintained separately by the War Office/Ministry of Supply, Admiralty and Air Ministry/Ministry of Aircraft Production on behalf of the three armed services (e.g. "ACR~", "AR~", "AT~", etc. for CRTs, receiving and transmitting valves used in army equipments, "NC~", "NR~" and "NT~" similarly for navy equipments and "VCR~", "VR~" and "VT~" etc. for air force equipments), in which three separate designations could in principle apply to the same valve (which often had at least one prototype commercial designation as well). These numbers generally have identical equivalents in both the North American, RETMA, and West European, Mullard–Philips, systems but they bear no resemblance to the assigned "CV" number.

Examples:

  • CV1988 = 6SN7-GT = ECC32 (not a direct equivalent as heater current is different and envelope is larger)
  • CV2729 = E80F – An SQ version of EF80 but with revised pin-out and a base screen substituted for the RF screen

The "CV4000" numbers identify special-quality valves though SQ valves CV numbered before that rule came in retain their original CV number:

  • CV4007 = E91AA – SQ version of 6AL5
  • CV4010 = E95F – SQ version of 6AK5 or EF95
  • CV4014 = M8083

The "M8" in the part number indicates that it was developed by the military:

  • M8083 – Sharp-cutoff pentode, Miniature 7-pin base (SQ version of EF91 = 6AM6 = Z77)
  • M8162 = 6060 – Dual high-μ triode used as RF amplifier/mixer in VHF circuits, Noval base (SQ versions of ECC81 = 12AT7 = B309)

The principle behind the CV numbering scheme was also adopted by the US Joint Army-Navy JAN numbering scheme which was later considerably expanded into the US Federal and then NATO Stock Number system used by all NATO countries. This part-identification system ensures that every particular spare part (not merely thermionic valves) receives a unique stock number across the whole of NATO irrespective of the source, and hence is not held inefficiently as separate stores. In the case of CV valves, the stock number is always of the format 5960-99-000-XXXX where XXXX is the CV number (with a leading 0 if the CV number only has 3 digits).

U.S. naming systems

One system prefixes a three-digit number with the letters "VT", presumably meaning "Vacuum Tube". Other systems prefix the number with the letters "JHS" or "JAN". The numbers following these prefixes can be "special" four-digit numbers, or domestic two- or three-digit numbers or simply the domestic North American "RETMA" numbering system. Like the British military system, these have many direct equivalents in the civilian types.

Confusingly, the British also had two entirely different "VT" nomenclatures, one used by the Royal Air Force (see the preceding section) and the other used by the General Post Office, responsible for post and telecommunications at the time, where it may have stood for "valve, telephone"; none of these schemes corresponded in any way with each other.

Examples:

  • "VT" numbering systems
  • North American VT90 = 6H6
  • British (RAF) VT90 – VHF Transmitting triode
  • British (GPO) VT90 = ML4 = CV1732 – Power triode
  • VT104 – RF pentode
  • VT105 – RF triode

Other systems

Since the 1920s, several manufacturers introduced proprietary numbering systems (examples), some of which grew into informal standards adopted by other manufacturers; the use was not rigorously systematic.

  • Low 800s – Mainly RF power tubes
  • High 800s – Mainly Mercury-vapor rectifiers
  • Low 900s – Mainly CRTs and phototubes
  • High 900s – Mainly Acorn tubes
  • 1600s – Mainly RCA
  • 4000s – Mainly Philips/Mullard/LaRadiotechnique/Valvo, RCA, STC (not coordinated)
  • 9000s – Mainly RCA VHF/UHF tubes

Several manufacturers used acronym prefixes to indicate the function or type for (mostly professional) tubes (ex.1, ex.2, ex.3, ex.4), or as a manufacturer's code:

List of American RETMA tubes

Note: Typecode explained above

LoVTList of American RETMA tubes

0 prefix - Gas-filled cold-cathode tubes

First character is numeric zero, not letter O.

LoVTList of American RETMA tubes0 prefix - Gas-filled cold-cathode tubes

Used in a similar way to a Zener diode, at higher voltages

Miniature 7-pin-based regulators: Letter order (A-B-C) indicates decreasing voltage; cathode on pins 2, 4, 7; anode on pins 1, 5

Octal-based regulators: Letter order (A-B-C) indicates increasing voltage; cathode on pin 2; anode on pin 5; jumper between pins 3 and 7 to unpower the device when the regulator is pulled from its socket

  • 0A2 = 150C2 – 150 V Voltage-regulator tube, Miniature 7-pin base; ruggedized version: 0A2-WA/6073
  • 0A3 = VR75 = M-OV/GEC QS75/40 = STC G75/2D – 75 V Voltage-regulator tube, Octal base
  • 0B2 = 108C1 = STC G108/1K – 105 V Voltage-regulator tube, Miniature 7-pin base; ruggedized version: 0B2-WA/6074/6627
  • 0B3 = VR90 – 90 V Voltage-regulator tube, Octal base
  • 0C2 – 75 V Voltage-regulator tube, Miniature 7-pin base
  • 0C3 = VR105 = STC G105/1D – 105 V Voltage-regulator tube, Octal base; ruggedized version: 0C3-W
  • 0D3 = VR150 = M-OV/GEC QS150/40 = STC G150/3D – 150 V Voltage-regulator tube, Octal base; ruggedized version: 0D3-W
  • 0E3 = 85A1 – 85 V Voltage-regulator tube, 3-pin Loctal base
  • 0G3 = 85A2 – 85 V Voltage-regulator tube, Miniature 7-pin base

LoVTList of American RETMA tubes0 prefix - Gas-filled cold-cathode tubes

Trigger tubes

  • 0A4-G (Z300T) – 25 mAavg, 100 mApeak Gas triode, Octal base, designed for use as a ripple control receiver - with the cathode tied to the midpoint of a series-resonance LC circuit across live mains, it would activate a relay in its anode circuit while fres is present
  • 0A5 – 1 kV, 10 Apeak Gas tetrode with a keep-alive (primer) electrode and a shield grid, Miniature 7-pin base, designed for relay drive and general switching

LoVTList of American RETMA tubes0 prefix - Gas-filled cold-cathode tubes

Rectifiers

  • 0Y4 – 300 V, 40 ≤ I ≤ 75 mA Half-wave gas rectifier with a starter anode, 5-pin Octal base
  • 0Z3 – 300 V, 30 ≤ I ≤ 75 mA Full-wave gas rectifier used in vibrator power supplies in early car radios, UY5 base
  • 0Z4 – 880 V, 30 ≤ I ≤ 90 mA Argon-filled, full-wave gas rectifier, 5-pin Octal base. Widely used in vibrator power supplies in early car radios

LoVTList of American RETMA tubes

1 prefix - 1 volt filament/heater tubes

LoVTList of American RETMA tubes1 prefix - 1 volt filament/heater tubes

1.25 volt DC filament tubes

These tubes have directly heated cathodes, usually running on a single NiCd cell; pentodes and heptodes specify the filament polarity because the suppressor grid is internally connected to the negative filament end; 1AD4, 1AG4, 1AG5, 1AK4 and 1AK5 pentodes have a split suppressor grid, its halves tied to the positive resp. negative filament end

  • 1E3 – UHF Triode, 220 mA filament, Noval base
  • 1AB5 – 1LN5 with higher transconductance and a 1.20 V/130 mA filament, Loctal base
  • 1AE4 – Sharp-cutoff pentode, 100 mA filament, Miniature 7-pin base

The following Pencil subminiature tubes were used in post-World War II walkie-talkies, pocket-sized portable radios, and hearing aids; all have all-glass envelopes 1+18 to 2 in (29 to 51 mm) long and with diameters of:

—Elliptical cross-section envelope with Flat-Press inline base/wire-ends: 0.285 by 0.366–0.4 in (7 by 9–10 mm)

—Round cross-section envelope with circular base/wire-ends: ca. 0.366–0.4 in (9–10 mm)

  • 1C8 – Heptode pentagrid converter with American grid topology, 40 mA filament, round/circular, 8-pin/wire-ends
  • 1D3 – Low-μ UHF triode, 300 mA filament, round/circular, 8-pin/wire-ends
  • 1E8 – Heptode pentagrid converter with American grid topology, 40 mA filament, Sub-Minar round/circular, 8-pin/wire-ends
  • 1Q6 – Diode + AF pentode, 40 mA filament, round/circular, 8-pin/wire-ends; similar to 1LD5/DAF26, 1S5/DAF91, but rated for lower voltages
  • 1S6 – Diode + sharp-cutoff pentode, 40 mA filament, round/circular, 8-pin/wire-ends
  • 1T6 – Diode + sharp-cutoff pentode, 40 mA filament, Sub-Minar round/circular, 8-pin/wire-ends
  • 1V5 – Power pentode, 40 mA filament, round/circular, 8-pin/wire-ends
  • 1V6/DCF60 – Triode/pentode oscillator/mixer, 40 mA filament, elliptical/inline, 7 long wire-ends
  • 1W5 – Sharp-cutoff pentode, 40 mA filament, round/circular, 8-pin/wire-ends
  • 1AC5 – Power pentode, 40 mA filament, Sub-Minar round/circular, 8-pin/wire-ends
  • 1AD4/DF62 – Shielded, sharp-cutoff RF pentode, 100 mA filament, elliptical/inline, 5 long wire-ends
  • 1AD5 – Sharp-cutoff pentode, 40 mA filament, round/circular, 8-pin/wire-ends
  • 1AE5 – Heptode pentagrid converter with American grid topology, 60 mA filament, elliptical/inline, 6 long wire-ends
  • 1AG4 – Power pentode, 40 mA filament, elliptical/inline, 5 long wire-ends
  • 1AG5 – Diode + sharp-cutoff pentode, 30 mA filament, elliptical/inline, 6 long wire-ends
  • 1AH4 – Shielded, semiremote-cutoff RF pentode, 40 mA filament, elliptical/inline, 5 long wire-ends
  • 1AJ5 – Diode + sharp-cutoff pentode, 40 mA filament, elliptical/inline, 6 long wire-ends
  • 1AK4 – Sharp-cutoff pentode, 20 mA filament, elliptical/inline, 5 long wire-ends
  • 1AK5 – Diode + sharp-cutoff pentode, 20 mA filament, elliptical/inline, 6 long wire-ends

More of these tubes are listed as equivalents under M-P D - 1.4 V filament/heater

LoVTList of American RETMA tubes1 prefix - 1 volt filament/heater tubes

1.4 volt DC filament/heater tubes

Designed for use in dry cell battery-only or in Three-way portable (AC/DC/Dry-cell) radio receivers; most are directly heated, pentodes and heptodes specify the filament polarity

  • 1A3/DA90Indirectly heated FM discriminator diode used as a detector in some portable AM/FM receivers, 150 mA heater, Miniature 7-pin base
  • 1A7-GT/DK32 – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 50 mA filament, Octal base, introduced in 1938; re-engineered variant of 1A6, 1D7-G
  • 1AF4 – Sharp-cutoff pentode, 25 mA filament, Miniature 7-pin base
  • 1AF5 – Diode + sharp-cutoff pentode, 25 mA filament, Miniature 7-pin base
  • 1B7-GT – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 100 mA filament, Octal base; re-engineered variant of 1C6, 1C7-G for shortwave use
  • 1B8-GT, 1D8-GT – Diode + triode + power pentode, 100 mA filament, Octal base with triode grid on top cap
  • 1C5-GT/DL35 – Power pentode, 100 mA filament, Octal base; similar to 3Q5-GT/DL33
  • 1E4-G (μ = 14), 1G4-GT/G (μ = 8.8) – AF triode, 50 mA filament, Octal base
  • 1G6-G, 1G6-GT – Dual power triode, 100 mA filament, Octal base
  • 1H5-GT/DAC32 – Diode + high-μ AF triode, 50 mA filament, Octal base with triode grid on top cap
  • 1N6-G – Diode + power pentode, 50 mA filament, Octal base
  • 1P5-G, 1P5-GT – Sharp-cutoff pentode, 50 mA filament, Octal base with control grid on top cap
  • 1R5/DK91 – Heptode pentagrid converter with American grid topology, anode voltage in the 45...90 volt range, 50 mA filament, Miniature 7-pin base; ruggedized version: 1R5-WA
  • 1R5-SF = 1AQ5 – 1R5/DK91 with a 25 mA filament
  • 1S4/DL91 – 270 mW AF power pentode Class-A amplifier, anode voltage in the 45...90 volt range, 100 mA filament, Miniature 7-pin base
  • 1S5/DAF91 – Diode + sharp-cutoff pentode used as detector and first AF amplifier, anode voltage in the 67...90 volt range, 50 mA filament, Miniature 7-pin base
  • 1S5-SF = 1S5T = 1AR5 – 1S5/DAF91 with a 25 mA filament
  • 1T4/DF91 – Remote-cutoff RF/IF pentode, 50 mA filament, Miniature 7-pin base; ruggedized version: 1T4-WA
  • 1T4-SF = 1AM4 – 1T4/DF91 with a 25 mA filament
  • 1T5-GT – AF beam power pentode, 50 mA filament, Octal base
  • 1U4/DF904/5910 – Sharp-cutoff RF/IF pentode, 50 mA filament, Miniature 7-pin base; ruggedized version: 1U4-WA
  • 1U5/DAF92 – Diode + AF pentode, 50 mA filament, Miniature 7-pin base; ruggedized version: 1U5-WA
  • 1U5-SF = 1AS5 – 1U5/DAF92 with a 25 mA filament
  • 1U6 – 1L6 with a 25 mA filament
  • 1W4 – Power pentode, 50 mA filament, Miniature 7-pin base
  • 1DN5 – Diode + remote-cutoff pentode, 50 mA filament, Miniature 7-pin base
  • 1LA4 – Power pentode, 50 mA filament; 1A5/DL31 with a Loctal base
  • 1LA6 (Loctal) and later 1L6 (Miniature 7-pin) – Heptode pentagrid converter with British grid topology, used in the Zenith Trans-Oceanic 7G605/8G005Y series shortwave radios, 50 mA filament
  • 1LB4 – Power pentode used in the T/O 8G005Y, 50 mA filament, Loctal base
  • 1LB6 – Heptode pentagrid converter, 50 mA filament, Loctal base
  • 1LC5 – Sharp-cutoff pentode, 50 mA filament, Loctal base
  • 1LC6 – 1LA6 with higher conversion transconductance, 50 mA filament, Loctal base
  • 1LD5/DAF26 – Diode + sharp-cutoff pentode used in the T/O 7G605/8G005Y, 50 mA filament, Loctal base
  • 1LE3 – Medium-μ triode used in the T/O 8G005Y, 50 mA filament, Loctal base
  • 1LG5 – Remote-cutoff RF/IF pentode, 50 mA filament, Loctal base
  • 1LH4 – Diode + high-μ AF triode, 50 mA filament; 1H5-GT/DAC32 with its top cap discarded and a Loctal base
  • 1LN5 – Sharp-cutoff pentode used in the T/O 7G605/8G005Y, 50 mA filament, Loctal base
  • 1SA6-GT – Semiremote-cutoff RF/IF pentode, 50 mA filament, single-ended tube (=no top cap), Octal base
  • 1SB6-GT – Diode + sharp-cutoff pentode, 50 mA filament, single-ended tube, Octal base

More of these tubes are listed as equivalents under M-P D - 1.4 V filament/heater

LoVTList of American RETMA tubes1 prefix - 1 volt filament/heater tubes

2 volt DC filament tubes

These tubes were made for home storage battery receivers manufactured during the early to mid-1930s; all are directly heated with a 2.0 volt DC filament despite the 1-prefix, intended to distinguish them from the 2.5 volt AC heated tubes listed below

  • 1A4 = 1A4P – Remote-cutoff pentode, suppressor grid internally tied to 60 mA filament negative or center-tap, UX4 base with control grid on top cap
  • 1A4T – Remote-cutoff tetrode; 1A4P without a suppressor grid
  • 1A6 (U6A base), 1D7-G (Octal base) – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 60 mA filament, up to only 10 MHz due to low heater power and consequent low emission in the oscillator section, also occasionally used as a grid-leak detector
  • 1B4 = 1B4P – Sharp-cutoff pentode, suppressor grid internally tied to the negative 60 mA filament end, UX4 base with control grid on top cap
  • 1B4T – Sharp-cutoff tetrode; 1B4P without a suppressor grid
  • 1B5 = 25S = 1B5/25S (U6A base), 1H6-G, 1H6-GT (Octal base) – Dual diode + medium-μ triode, 60 mA filament
  • 1C4 – Remote-cutoff pentode, 120 mA filament, UX4 base with control grid on top cap
  • 1C6 (U6A base), 1C7-G (Octal base) – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 120 mA filament; 1A6, 1D7-G with double the heater power and double the frequency range
  • 1D4 – Power pentode, 240 mA filament, UY5 base
  • 1D5-G = 1D5-GP – 1A4P with an Octal base
  • 1D5-GT – 1A4T with an Octal base (Note: This is a shouldered "G" Octal, not a cylindrical "GT" Octal)
  • 1E5-G = 1E5-GP – 1B4P with an Octal base
  • 1E5-GT – 1B4T with an Octal base (Note: This is a shouldered "G" Octal, not a cylindrical "GT" Octal)
  • 1E7-G, 1E7-GT – Dual power pentode used as a driver when parallel-connected, or as a push-pull output, 240 mA filament, Octal base
  • 1F4 (UY5 base), 1F5-G (Octal base) – Power pentode, suppressor grid internally tied to the negative 120 mA filament end
  • 1F6 (U6A base), 1F7-G (Octal base) – Dual diode + sharp-cutoff pentode with control grid on top cap, suppressor grid internally tied to the negative 60 mA filament end
  • 1G5-G – Power pentode, suppressor grid internally tied to the negative 120 mA filament end, Octal base
  • 1H4-G, 1H4-GT – Medium-μ triode, 60 mA filament, can be used as a power triode; type 30 (=upgraded type 01-A) with an Octal base
  • 1H6-G, 1H6-GT – See 1B5/25S
  • 1J5-G – AF power pentode, suppressor grid internally tied to the negative 120 mA filament end, Octal base; similar to 950
  • 1J6-G, 1J6-GT – Dual power triode, 240 mA filament; type 19 with an Octal base
  • 1K4 (UX4 base), 1K5-G (Octal base) – AF power pentode with control grid on top cap, suppressor grid internally tied to the negative 120 mA filament end
  • 1K6 (U6A base), 1K7-G (Octal base) – Dual diode + AF power pentode with control grid on top cap, suppressor grid internally tied to the negative 120 mA filament end
  • 1L5-G – Power pentode, suppressor grid internally tied to the negative 240 mA filament end, Octal base
  • 1M5-G – Remote-cutoff pentode with control grid on top cap, suppressor grid internally tied to the negative 120 mA filament end, Octal base

LoVTList of American RETMA tubes1 prefix - 1 volt filament/heater tubes

One-volt ballast tubes

Used to adapt the above 2 volt DC filament tubes to 2-cell dry batteries

  • 1D1 – 240 mA filament
  • 1D2, 1G1 – 420 mA filament
  • 1A1 – 490 mA filament
  • 1R1, 1Y1 – 540 mA filament
  • 1K1 – 550 mA filament
  • 1T1, 1V1 – 560 mA filament
  • 1J1 – 620 mA filament
  • 1E2, 1S1, 1W1 – 660 mA filament
  • 1F1 – 720 mA filament
  • 1U1 – 740 mA filament
  • 1C1 – 745 mA filament
  • 1Z1 – 900 mA filament

LoVTList of American RETMA tubes1 prefix - 1 volt filament/heater tubes

CRT anode rectifiers

  • 1AJ2Compactron CRT EHT rectifier, 1.25 V/200 mA filament
  • 1AY2Duopin 2-pin base CRT EHT rectifier; similar to 1B3-GT/DY30
  • 1B3-GT/1G3-GT/DY30 = 1Ц7С1C7S – CRT EHT rectifier, 1.25 V filament, peak inverse voltage of 30 kV, anode current 2 mA average, 17 mA peak, Octal base, common in 1950s and early 1960s monochrome TV receivers; derived from the earlier industrial type 8016
  • 1BC2 – CRT EHT rectifier, 1.25 V/200 mA filament, Noval base
  • 1BC2A, 1BC2B – 1BC2 with internal X-radiation shielding
  • 1BG2/DY51 – 15 kV Subminiature CRT EHT rectifier used in portable TV receivers, half-indirect 1.4 V/575 mA heater, all-glass, heater wires on one end, anode wire on the other
  • 1BQ2/DY802 – 20 kV CRT EHT rectifier, half-indirect 1.4 V/600 mA heater, Noval base, silicone-coated envelope to prevent flush-over in high-humidity and low atmospheric-pressure conditions
  • 1BY2Compactron CRT EHT rectifier, 1.25 V/200 mA filament
  • 1BY2A – 1BY2 with internal X-radiation shielding
  • 1H2 – CRT EHT rectifier, half-indirect 1.4 V/550 mA heater, Noval base
  • 1J3-GT/1K3-GT – CRT EHT rectifier, Octal base; 1B3-GT/DY30 with filament-anode shorting protection
  • 1S2/DY86 = 1Ц21П1C21P – 22 kV, 800 µA Half-indirectly heated CRT EHT rectifier, Noval base with anode on top cap; 6S2/EY86 with a 1.4 V/550 mA heater
  • 1T2 = Brimar R16 – Subminiature CRT EHT rectifier, 1.4 V/140 mA filament, filament wires on one end, anode wire on the other
  • 1V2 – CRT EHT rectifier, 625 mV/300 mA filament, Miniature 7-pin base
  • 1X2 – CRT EHT rectifier, 1.25 V/200 mA filament, Noval base
  • 1X2A, 1X2B, 1X2C – 1X2 with internal X-radiation shielding
  • 1Y2 – 50 kVPIV, 10 mApeak, 2 mAavg CRT EHT rectifier usable up to 1 MHz, 1.5 V/290 mA filament, UX4 base
  • 1Z1 – CRT EHT rectifier, 0.7 V/180 mA filament, Octal base
  • 1Z2 – CRT EHT rectifier, 1.25 V/265 mA filament, Noval base

LoVTList of American RETMA tubes

2 volt heater/filament tubes

Some 6-prefix tubes were also available as 2-prefix, for television receivers with series heater strings (see below)

LoVTList of American RETMA tubes2 volt heater/filament tubes

2.5 volt AC heater tubes

Tubes used in AC-powered radio receivers since the early 1930s; most are indirectly heated

  • 2A3 – 15 W Directly heated AF power triode now used in audiophile gear, 2.5 A filament, UX4 base
  • 2A5 – Power pentode, U6A base; types 42, 6F6 with a 2.5 V/1.75 A heater
  • 2A6 – Dual diode + high-μ triode, U6A base with control grid on top cap; types 75, 6B6-G with a 2.5 V/800 mA heater
  • 2A7 – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap, U7A base; 6A7, 6A8, 12A8 with a 2.5 V/800 mA heater
  • 2B6Triple-Twin AF signal + zero bias power triode, 2.25 A heater, internally connected as a cathode follower like today's Darlington transistors; cf. 295, 6AC6, 6B5, 6N6-G
  • 2B7 – Dual diode + remote-cutoff pentode, U7A base with control grid on top cap; 6B7, 6B8-G with a 2.5 V/800 mA heater
  • 2E5 – Top-view, "Magic Eye"-type tuning indicator; 2G5 with a sharp-cutoff driver triode; 6E5 with a 2.5 V/800 mA heater
  • 2G5 – Top-view, "Magic Eye"-type tuning indicator; 2E5 with a remote-cutoff driver triode; 6G5/6U5 with a 2.5 V/800 mA heater

Thyratrons

  • 2A4-GDirectly heated triode thyratron, 2.5 A filament, Octal 7-pin base
  • 2B4 = 885 – Indirectly heated triode thyratron used in DuMont oscilloscopes as a sweep generator; 6Q5-G = 884 with a 2.5 V/2.5 A heater and a UY5 base
  • 2C4 – Indirectly heated triode thyratron used in portable equipment, 650 mA heater, Miniature 7-pin base

LoVTList of American RETMA tubes2 volt heater/filament tubes

CRT anode rectifiers

  • 2AS2, 2AH2/2AS2A/2BU2Compactron CRT EHT rectifier, 2.5 V/330 mA heater
  • 2AV2 – CRT Focus HV rectifier, 1.8 V/225 mA filament, Noval base
  • 2X2 = 879 = 2Ц2С2C2S – CRT EHT rectifier, half-indirect 2.5 V/1.75 A heater; similar to 1B3, 1S2/DY86 except for heater ratings
  • 2X2A – 2X2, shock resistant up to 250 g

More of these tubes are listed as equivalents under M-P K - 2.0 V heater

LoVTList of American RETMA tubes

3 volt heater/filament tubes

Many 6-prefix tubes were also available as 3-prefix with a 3.15 V heater with twice the heater current, for television receivers with series heater strings

LoVTList of American RETMA tubes3 volt heater/filament tubes

2.8 volt DC filament tubes

These tubes are directly heated with a center-tapped filament, so they can be switched to 1.4 V for use in Three-way portable (AC or DC mains, or dry batteries) radio receivers

  • 3A4/DL93 – 700 mW RF/AF power pentode, 100 resp. 200 mA filament, Miniature 7-pin base
  • 3A5/DCC90 – 2×1 W, 40 MHz Dual RF power triode, 110 resp. 220 mA filament, Miniature 7-pin base
  • 3A8-GT – Diode + triode + pentode, 50 resp. 100 mA filament with internal shield tied to center-tap, Octal base; 1H5-GT/DAC32 + 1N5-GT/DF33 in one envelope
  • 3B4/DL98 – 1.25 W, 100 MHz RF power pentode, 2.5 V/165 mA resp. 1.25 V/330 mA filament with suppressor grid tied to center-tap, Miniature 7-pin base
  • 3B5-GT – AF beam power pentode, 67.5 V anode voltage, 50 resp. 100 mA filament with beam plates tied to center-tap, Octal base
  • 3B7 – 1.4 W, 125 MHz Dual VHF power triode, 110 resp. 220 mA filament, Loctal base
  • 3C4/DL96 – 200 mW AF power pentode, 25 resp. 50 mA filament with suppressor grid tied to center-tap, Miniature 7-pin base
  • 3C6 = Philco XXB – Medium-μ dual triode, 50 resp. 100 mA filament, Loctal base
  • 3E5 – 200 mW AF beam power pentode, 25 resp. 50 mA filament with beam plates tied to center-tap, Miniature 7-pin base
  • 3E6 – Sharp-cutoff pentode, 50 resp. 100 mA filament with internal shield tied to center-tap, Loctal base
  • 3LE4 – 325 mW AF power pentode, 25 resp. 50 mA filament with suppressor grid tied to center-tap, Loctal base
  • 3LF4 – 3Q5-GT/DL33 with a Loctal base
  • 3Q4/DL95 – 270 mW AF power pentode, 25 resp. 50 mA filament with suppressor grid tied to center-tap, Miniature 7-pin base
  • 3Q5-GT/DL33 – 330 mW AF beam power pentode, 50 resp. 100 mA filament with beam plates tied to center-tap, Octal base
  • 3S4/DL92 – 1S4/DL91 AF power pentode with the suppressor grid tied to the center-tap of the 50 resp. 100 mA filament, Miniature 7-pin base
  • 3S4-SF = 3S4T = 3W4 – 3S4/DL92 with a 2.8 V/25 mA resp. 1.4 V/50 mA filament
  • 3V4/DL94 – 3Q4/DL95 AF power pentode with a different Miniature 7-pin base pinout; ruggedized version: 3V4-WA

More of these tubes are listed as equivalents under M-P D - 1.4 V filament/heater

LoVTList of American RETMA tubes3 volt heater/filament tubes

CRT anode rectifiers

  • 3A3/3B2/3AW3 – 30 kVPIV, 88 mApeak, 1.7 mAavg CRT EHT rectifier for color TV, half-indirect 3.15 V/220 mA heater, Octal base
  • 3AT2Compactron CRT EHT rectifier for analog color TV receivers, half-indirect 3.15 V/220 mA heater
  • 3AT2B – 3AT2 with internal X-radiation shielding
  • 3AW2Compactron CRT EHT rectifier for analog color TV receivers, half-indirect 3.15 V/350 mA heater
  • 3AW2A – 3AW2 with internal X-radiation shielding
  • 3BF2 - Compactron CRT EHT rectifier for analog color TV receivers, 3.6 V/225 mA heater
  • 3BL2Compactron CRT EHT rectifier for analog color TV receivers, 3.3 V/285 mA filament
  • 3BL2A – 3BL2 with internal X-radiation shielding
  • 3BM2Compactron CRT EHT rectifier for analog color TV receivers, 3 V/300 mA filament
  • 3BM2A – 3BM2 with internal X-radiation shielding
  • 3BN2Compactron CRT EHT rectifier for analog color TV receivers, half-indirect 3.15 V/300 mA heater
  • 3BN2A – 3BN2 with internal X-radiation shielding
  • 3BS2Compactron CRT EHT rectifier for analog color TV receivers, half-indirect 3.15 V/480 mA quickstart heater
  • 3BS2A, 3BS2B – 3BS2 with internal X-radiation shielding
  • 3BT2Compactron CRT EHT rectifier for analog color TV receivers, half-indirect 3.15 V/480 mA quickstart heater
  • 3BT2A – 3BT2 with internal X-radiation shielding
Note: All subsequent CRT EHT rectifiers were designed after the 1967 GE scandal and had internal X-radiation shielding right from the start
  • 3BW2Compactron CRT EHT rectifier for analog color TV receivers, half-indirect 3.15 V/480 mA quickstart heater, has a diffusion-bonded cathode, which prevents anode-to-cathode arcing caused by emissive particles being pulled from the cathode coating by the high electrostatic field
  • 3CA3 – CRT EHT rectifier for analog color TV receivers, Octal base, half-indirect 3.6 V/225 mA heater
  • 3CN3 – CRT EHT rectifier with a diffusion-bonded cathode for analog color TV receivers, Octal base, half-indirect 3.15 V/480 mA quickstart heater
  • 3CU3 – CRT EHT rectifier for analog color TV receivers, Octal base, 3.15 V/280 mA filament
  • 3CZ3 – CRT EHT rectifier for analog color TV receivers, Octal base, half-indirect 3.15 V/480 mA quickstart heater
  • 3DA3 – CRT EHT rectifier, 3.15 V/480 mA heater, Octal base
  • 3DB3/3CY3 – CRT EHT rectifier, 3.15 V/245 mA heater, Octal base
  • 3DC3 – CRT EHT rectifier, 3.15 V/280 mA heater, Octal base; upgraded 3CU3A
  • 3DH3 – CRT EHT rectifier, 3.15 V/480 mA heater, Octal base

More of these tubes are listed as equivalents under M-P G - Miscellaneous

  • 3DG4 – 1.05 kV, 2×1.2 A Full-wave rectifier, 3.3 V/3.8 A filament, 5-pin Octal base

LoVTList of American RETMA tubes

4 volt heater/filament tubes

Some 6-prefix tubes were also available as 4-prefix with a 4.2 V heater with 1.5 times the heater current, for television receivers with series heater strings (see below)

4 volt DC filament tubes

  • 4A6-G – Directly heated, dual power triode, center-tapped 4.0 V/60 mA resp. 2.0 V/120 mA filament, Octal base

Ballast tubes

  • 4A1 – 300 mA filament

LoVTList of American RETMA tubes

5 volt heater/filament tubes

Some 6-prefix tubes were also available as 5-prefix, for television receivers with series heater strings (see below)

5 volt DC filament tubes

  • 5A6 – 5 W, 100 MHz Directly heated VHF beam power pentode, center-tapped 5.0 V/230 mA resp. 2.5 V/460 mA filament, Noval base

Full-wave rectifiers

These tubes all have a 5.0 V filament/heater

  • 5R4-G (Bakelite base), 5R4-GY, 5R4-GYA, 5R4-GYB (Micanol base) – 2.8 kV, 2×325 mA Directly heated full-wave rectifier, 2 A filament, 5-pin Octal base; avionics versions: 5R4-WGA, 5R4-WGB
  • 5U4-G/GZ31 = 5Ц3С5C3S (ST-16 envelope, 5-pin Octal), 5U4-GB (T-12 envelope, 5-pin Octal), 5X4-G (ST-16 envelope, 8-pin Octal), 5Z3 (ST-16 envelope, UX4) – 1.55 kV, 2×675 mA Directly heated full-wave rectifier, 3 A filament; ruggedized version: 5U4-WG/5931
  • 5V3A/5AU4 – 1.55 kV, 2×415 mA Directly heated full-wave rectifier, 3.75 A filament, Octal base
  • 5V4/GZ32 – 1.4 kV, 175 mA Full-wave rectifier, half-indirect 2 A heater, 5-pin Octal base
  • 5Y3, 5Y3-G, 5Y3-GA, 5Y3-GT – 1.4 kV, 2×400 mApeak Directly heated full-wave rectifier, 2 A filament; type 80 with a 5-pin Octal base; ruggedized version: 5Y3-WGT
  • 5Y3-GB – Half-indirectly heated variant of 5Y3-GT; ruggedized versions: 6087, 6106, 6853
  • 5AR4/GZ34 – 1.7 kV, 2×125 mA Indirectly heated full-wave rectifier, 1.9 A heater, 5-pin Octal base
  • 5AS4 – 5U4-GB with a ST-16 envelope, 8-pin Octal base
  • 5AW4 – 1.55 kV, 2×750 mA Directly heated full-wave rectifier, 3.7 A filament, 5-pin Octal base
  • 5AX4-GT – 1.4 kV, 2×525 mA Directly heated full-wave rectifier, 2.5 A filament, 5-pin Octal base
  • 5AZ4 – 1.4 kV, 125 mA Directly heated full-wave rectifier, 2 A filament, Loctal base
  • 5BC3, 5BC3A – 1.7 kV, 1 A Directly heated full-wave rectifier, 3 A filament, Novar base
  • 5CU4 – 800 V, 1.3 A Indirectly heated full-wave rectifier, 3.5 A heater, 5-pin Octal base
  • 5DJ4 – 1.7 kV, 2×1 A Directly heated full-wave rectifier, 3 A filament, Octal base

More of these tubes are listed as equivalents under M-P G - 5.0 V heater

LoVTList of American RETMA tubes

6 volt heater tubes

These tubes all have a 6.3 V filament/heater. Note: 6-prefix tubes with center-tapped heaters are listed under 300 mA series heater tubes

  • 6A3 – 15 W AF Power triode, 1 A heater, UX4 base
  • 6A4 = Raytheon LA (Commonly branded 6A4/LA) – Directly heated power pentode, 300 mA filament with suppressor grid internally tied to a center-tap, UY5 base
  • 6A5-G – 15 W Power triode, 1 A heater with cathode internally tied to a center-tap, Octal base
  • 6A6 – 2×5.5 W Dual power triode used as a Class-A audio driver or a Class-B audio output, U7B base; 6.3 V/800 mA heater version of type 53 which had a 2.5 V/2 A heater; Octal version: 6N7
  • 6A7 (U7A base), 6A7S (U7A base with external shield tied to cathode), 6A8-G/PH4 (Octal base), 6A8-GTX (Ceramic base) – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap; 2A7, 12A8 with a 6.3 V/800 mA heater; Loctal version: 7B8; similar to M-OV/GEC X63
  • 6B3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Noval base with cathode on top cap
  • 6B4-G – 15 W Power triode, 1 A heater, Octal base
  • 6B5 (U6A base), 6N6-G (Octal base) – Triple-Twin AF signal + 4-watts zero bias power triode, internally connected as a cathode follower like today's Darlington transistors, 800 mA heater; cf. 295, 2B6, 6AC6
  • 6B6-G – Dual diode + high-μ triode, grid on top cap, 300 mA heater; type 75 with an Octal base, later 6SQ7 (without control grid top cap); Miniature 7-pin version: 6AV6/EBC91
  • 6B7 (U7A base), 6B8, 6B8-G, 6B8-GT (Octal base) – Dual diode + semiremote-cutoff pentode with control grid on top cap. The diodes were mostly used as AM detector and AVC rectifier in superheterodyne receivers. The pentode was used as variable-gain IF or AF amplifier, or in reflex receivers - in a typical 2B7/6B7/6B8-G reflex circuit, the IF signal from the converter is injected into the pentode and amplified. The diodes then extract the AF signal from the RF signal. The AF signal is then re-injected into the pentode, amplified, and sent to the audio output tube;[113] 2B7 with a 6.3 V/300 mA heater; similar to EBF32
  • 6B10Compactron Dual diode + medium-μ dual triode used as horizontal phase detector and horizontal oscillator, 600 mA heater
  • 6C4/EC90 – 3.6 W, 150 MHz small-power VHF triode, single 12AU7/ECC82 system, 150 mA heater, Miniature 7-pin base; avionics versions: 6C4-W, 6C4-WA/6100
  • 6C5, 6C5-G, 6C5-GT – Triode, 300 mA heater, 6-pin Octal base
  • 6C6 (U6A base), 6J7-G/EF37 (Octal base) – Dual-control, sharp-cutoff RF pentode used as tuned RF amplifier or biased detector or AF amplifier, also used in test equipment, 300 mA heater, control grid on top cap; derived from type 57, which had a 2.5 volt heater; similar to types 1603, 77 and Octal type 6SJ7 (control grid on pin 4)
  • 6C7 – Dual diode + medium-μ triode used as renewal type for Majestic receivers, 300 mA heater, U7A base with shield on pin 3 and grid on top cap; similar to later Octal types 6R7 and 6SR7
  • 6C8-G – Dual triode, 300 mA heater, Octal base with one control grid on top cap
  • 6C9 – VHF Dual tetrode, 400 mA heater, B10G Decar base (=Noval plus center pin)
  • 6C10Compactron Triple high-μ triode, 600 mA heater – not related to the Mazda/EdiSwan 6C10 triode-hexode
  • 6D4 – 25 mAavg, 100 mApeak Indirectly heated, Argon triode thyratron, negative starter voltage, 250 mA heater, Miniature 7-pin base, found an additional use as a 0 to 10 MHz noise source, when operated as a diode (starter tied to cathode) in a transverse 375 G (37.5 mT) magnetic field. Sufficiently filtered for "flatness" ("white noise") in a band of interest, such noise was used for testing radio receivers, servo systems and occasionally in analog computing as a random value source
  • 6D6 (U6A base), 6U7-G (Octal base) – Dual-control, remote-cutoff RF pentode used as an IF amplifier or as a mixer, also used in test equipment, control grid on top cap, 300 mA heater; derived from type 58, which had a 2.5 volt heater; similar to types 78, 6K7/EF39 and 6SK7 (control grid on pin 4)
  • 6D7 – Sharp-cutoff pentode; 6C6, 6J7-G with U7A base with shield on pin 5 and control grid on top cap
  • 6D8-G – Heptode pentagrid converter with British grid topology and control (#4) grid on top cap, used in pre-war 6-volt farm radios, 150 mA heater, Octal base; similar to 6A8
  • 6D10Compactron Triple high-μ triode used as oscillator, mixer, amplifier or AFC reactance[68] tube, 450 mA heater
  • 6E5 – Top-view, "Magic Eye"-type tuning indicator, U6A base; 6G5/6U5 with a sharp-cutoff driver triode; 2E5 with a 6.3 V/300 mA heater
  • 6E5-M – Top-view, "Magic Eye"-type tuning indicator, 150 mA heater, Miniature 7-pin base; similar to Japanese 6M-E5
  • 6E6 – Dual power triode used in car radios, 600 mA heater, U7A base
  • 6E7 – Remote-cutoff pentode, 300 mA heater; 6D6, 6U7-G with U7A base with shield on pin 5 and control grid on top cap
  • 6E8-G – Triode/hexode oscillator/mixer, 300 mA heater, Octal base with hexode control grid #1 on top cap
  • 6F4 – 1.2 GHz Acorn UHF triode used as an oscillator, 225 mA heater
  • 6F5, 6F5-G, 6F5-GT – High-μ triode, 300 mA heater, Octal base with control grid on top cap, equal to triode section of 6Q7
  • 6F6 (Metal envelope), 6F6-G (Shouldered Tube glass envelope; M-OV/GEC KT63), 6F6-GT (Glass Tubular envelope) – 11 W AF Power pentode, 700 mA heater, Octal base, sometimes used as a transformer-coupled audio driver for 6L6-GC and 807 when those tubes were used in Class-AB2 or Class-B amplifiers, also used as a Class-C oscillator/amplifier in transmitters; type 42 with an Octal base
—Single-ended Class-A circuit: 9 watts max.
—Push-pull Class-A circuit: 11 watts max.
—Push-pull Class-AB2 circuit: 19 watts max.
  • 6F7 (U7A base), 6P7-G (Octal base) – Common cathode, medium-μ triode + remote-cutoff pentode used as triode/pentode oscillator/mixer, or as combination IF amplifier (pentode) and AM detector or AF amplifier (triode), 300 mA heater, U7A base with the pentode control grid on top cap
  • 6F8-G – Dual medium-μ triode, 600 mA heater, Octal base with one control grid on top cap; two 6J5 in one envelope
  • 6G5/6U5 (U6A base), 6G5-G/6U5-G (Octal base) – Top-view, "Magic Eye"-type tuning indicator; 6E5 with a remote-cutoff driver triode; 2G5 with a 6.3 V/300 mA heater
  • 6G6-G – 2.75 W Power pentode used in pre-war 6-volt farm radios, 150 mA heater, Octal base; Miniature 7-pin version: 6AK6
  • 6G8-G – Dual diode + remote-cutoff pentode used as detector and first AF amplifier in Australian 1940s radios, 300 mA heater, Octal base with control grid on top cap
  • 6G11Compactron Dual-control, sharp-cutoff pentode + 6.5-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 1.2 A heater
  • 6H4-GT – 100 V/4mA Diode, 150 mA heater, 5-pin Octal base
  • 6H5 – Top-view, "Magic Eye"-type tuning indicator, 300 mA heater, U6A base; 6G5/6U5 with an extra grid tied to the cathode and a fixed 90° shadow oppopsite the controllable one
  • 6H6 = 6Х6С6H6S ("Stubby" metal envelope), 6H6-G, 6H6-GT (Glass envelope) – Dual diode, 300 mA heater, Octal base; similar to EB34, M-OV/GEC D63, RFT HF/OSW3109
  • 6H7S – Triode + power pentode with a metal particles spray-shielded envelope, 500 mA heater, U7A base with triode control grid on top cap
  • 6H8-G – Common cathode dual diode + pentode, 300 mA heater, Octal base with control grid on top cap
  • 6J4/EC98 = 6С2П6S2P – UHF triode used in grounded-grid amplifiers, 400 mA heater, Miniature 7-pin base; ruggedized version: 6J4-WA/8532
  • 6J5 (Metal envelope), 6J5-G (Shouldered Tube glass envelope), 6J5-GT = 6С2С6S2S (Glass Tubular envelope), 6J5-GTX (Ceramic base) – Medium-μ triode; 12J5-GT with a 6.3 V/300 mA heater; similar to M-OV/GEC L63; avionics version: 6J5-WGT
  • 6J6/ECC91 – 600 MHz Dual VHF triode with common cathode, 450 mA heater, Miniature 7-pin base; ruggedized versions: 6J6-W, 6J6-WA, 6J6L/6927, 6030
  • 6J7, 6J7-G/EF37, 6J7-GT, 6J7-GTX (Ceramic base) – See 6C6
  • 6J8-G, 6J8-GA – Triode/heptode oscillator/mixer, 300 mA heater, Octal base with heptode control grid #1 on top cap
  • 6J9 – Triple VHF triode used as Autodyne mixer in FM tuners, 450 mA heater, B10G Decar base (=Noval plus center pin 10 for cathodes 1 and 2)
  • 6J10/6Z10Compactron Dual-control pentode + 10-watts power pentode used as FM quadrature demodulator and AF power amplifier, 950 mA heater; similar to 6AD10
  • 6J11Compactron Dual sharp-cutoff IF pentode, 800 mA heater
  • 6K4 (6AK4/EC70) – 750 mW, 500 MHz Ruggedized, subminiature medium-μ UHF triode, 150 mA heater, all-glass round cross-section envelope, chaotic 5-pin/wire-ends
  • 6K5-G, 6K5-GT – High-μ triode, 300 mA heater, 7-pin Octal base with grid on top cap
  • 6K6-G, 6K6-GT – 8.5 W Power pentode, 400 mA heater; type 41 with an Octal base
—Single-ended Class-A circuit: 0.35 to 4.5 watts
—Push-pull Class-A circuit: 10.5 watts max.
  • 6K7, 6K7-G/PF9 (EF39), 6K7-GT, 6K7-GTX (Ceramic base) – Dual-control, remote-cutoff RF pentode, 300 mA heater, 7-pin Octal base with control grid on top cap. Most common commercial uses were as an IF amplifier or as a superheterodyne mixer. Also used in test equipment; type 78 with an Octal base, later 6SK7 (control grid on pin 4)
  • 6K8, 6K8-G, 6K8-GT, 6K8-GTX (Ceramic base) – Triode/hexode oscillator/mixer introduced in 1938, Octal base with hexode control grid #1 on top cap; 12K8 with a 6.3 V/300 mA heater
  • 6K11/6Q11Compactron 2× High-μ + 1× medium-μ triple triode used as a combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, 600 mA heater
  • 6L4Acorn UHF triode used as an oscillator, 225 mA heater
  • 6L5-G – Medium-μ triode available only in ST envelope, 150 mA heater, 6-pin Octal base; similar to 6J5-G
  • 6L6 (Metal envelope), 6L6-G (Shouldered Tube glass envelope; EL37), 6L6-GT* (Glass Tubular envelope) – AF Beam power tetrodes, 900 mA heater, Octal base
    The original types 6L6 and 25L6 were derived from the M-OV/GEC N40 and introduced in April 1936 as the first American-made, commercially available beam power tetrodes. Both types were branded with the L6 ending to signify their (then) uniqueness among audio output tubes. However, this is the only similarity between the two tubes (6W6-GT is the 6.3 volt heater version of 12L6-GT, 25L6-GT and 50L6-GT).
    There are variants with e.g. thicker and/or ultra-black coated anode sheets, grids of larger diameter wire and/or with cooling fins; all variants up to revision A have the same maximum output ratings:
—Single-ended Class-A circuit: 11.5 watts
—Push-pull Class-A circuit: 14.5 watts
—Push-pull Class-AB1 circuit: 34 watts
—Push-pull Class-AB2 circuit: 60 watts
  • 6L6-GA – Post-war version of 6L6-G, smaller Shouldered Tube ST-14 shaped envelope
  • 6L6-GAY – 6L6-GA with a Micanol base for improved RF performance
  • 6L6-WGA/5932 – Ruggedized version of 6L6-GA
  • 6L6-GB – Post-war upgraded version in a cylindrical glass envelope; similar to 5881
  • 6L6-GTB – 6L6 with a Glass Tubular envelope and a higher power rating; the 6L6-GTB can always replace the 6L6, 6L6-G, and 6L6-GT, but a 6L6-GTB running at maximum rating should not be replaced with a lower subvariant
  • 6L6-WGB – Ruggedized version of 6L6-GB
  • 6L6-GC – Final and highest-powered audio version of the tube. Max. output ratings:
—Single-ended Class-A circuit: 17.5 watts
—Push-pull Class-A circuit: 32 watts
—Push-pull Class-AB1 circuit: 55 watts
—Push-pull Class-AB2 circuit: 60 watts
  • 6L6-GX – Class-C oscillator/amplifier used in transmitters, low loss ceramic base for improved RF performance, max. output 30 watts
  • 6L7, 6L7-G – Remote-cutoff heptode pentagrid converter with American grid topology but control (#1) grid on top cap (requiring a separate oscillator – usually 6C5 – on the #3 grid), popular in late 1930s console radios, 300 mA heater, Octal base. Because of low conversion transconductance, radios using 6L7 typically have at least two IF amplifiers and/or a tuned RF pre-amplifier
  • 6M3 – CRT horizontal deflection output booster/damper/efficiency diode, 3 A heater, Octal base with cathode on top cap
  • 6M5/EL80 – 9 W AF power pentode used as Class-A or AB output amplifiers of 1950s Australian radiograms, 710 mA heater, Noval base; similar to 6BQ5/EL84
  • 6M6-G – Power pentode, 1.2 A heater, Octal base
  • 6M7-G – Remote-cutoff RF pentode with a metal particles spray-shielded envelope, 300 mA heater, Octal base with control grid on top cap
  • 6M8-GT – Common cathode diode + AF triode + RF/IF pentode, 600 mA heater, Octal base with pentode control grid on top cap
  • 6M11Compactron Dual triode + IF pentode, 750 mA heater
  • 6N3/EY82 – 850 V, 360 mA Half-wave rectifier, 900 mA heater, Noval base
  • 6N4 – UHF Triode, 200 mA heater, Miniature 7-pin base
  • 6N5 – See 6AB5/6N5
  • 6N6-G, 6N6-MG – See 6B5
  • 6N7, 6N7-G, 6N7-GT = 6Н7С6N7S – 2×5.5 W Dual power triode used as Class-A audio driver or as Class-B power output, 800 mA heater, max. output (Class-B): 10 watts; 6A6 with an Octal base
  • 6N8/EBF80 – Dual diode + remote-cutoff pentode used as detector plus RF or AF amplifier in radios, 300 mA heater, Noval base
  • 6P5-G/GT – Medium-μ triode, 300 mA heater, often used as cathode follower driver for the 6AC5-G zero bias power triode; type 76 with an Octal base
  • 6P6 – RF Power pentode, 700 mA heater, U6A base
  • 6P7-G – See 6F7
  • 6P8-G – Triode/hexode oscillator/mixer, 800 mA heater, Octal base with hexode control grid #1 on top cap
  • 6Q4/EC80 – VHF Triode, 430 mA heater, Noval base
  • 6Q5-G = 884 – Triode gas thyratron used in DuMont oscilloscopes as a sweep generator; 2B4 = 885 with a 6.3 V/600 mA heater and an Octal base
  • 6Q6-G – Diode + triode, 150 mA heater, Octal base with grid on top cap
  • 6Q7, 6Q7-G, 6Q7-GT – Common cathode dual diode + high-μ AF triode, μ = 70, 300 mA heater, Octal base with control grid on top cap
  • 6Q11 – See 6K11/6Q11
  • 6R3/EY81 – 4.5 kV, 150 mA CRT horizontal deflection output booster/damper/efficiency diode, 810 mA heater, Noval base with cathode on top cap
  • 6R4/EC81 – UHF oscillator triode, 175 mA heater, Noval base
  • 6R6-G – Remote-cutoff pentode, 300 mA heater, Octal base with control grid on top cap
  • 6R7, 6R7-G, 6R7-GT – Dual diode + medium-μ triode, μ = 16, 300 mA heater, Octal base with control grid on top cap; Miniature 7-pin version: 6BF6
  • 6R8 – Triple diode + low-μ triode used as AM/FM demodulator and AF amplifier, 450 mA heater, Noval base
  • 6S2/EY86 – 22 kV, 800 µA Half-indirectly heated CRT EHT rectifier, Noval base with anode on top cap; 1S2/DY86 with a 6.3 V/90 mA heater
  • 6S4, 6S4A – Medium-μ triode used as CRT vertical deflection amplifier, 600 mA heater, Noval base
  • 6S5 – Tuning indicator, 300 mA heater, U6A base
  • 6S6-GT – Remote-cutoff RF pentode, 450 mA heater, 7-pin Octal base with control grid on top cap
  • 6S7, 6S7-G – Remote-cutoff RF pentode used in pre-war 6-volt farm radios, 150 mA heater, Octal base with control grid on top cap; similar to 6D6, 6K7
  • 6S8-GT – Triple diode + high-μ triode sharing a cathode with two of the diodes, used as a combined AM detector/AVC rectifier/FM ratio detector/AF amplifier in AM/FM radios, 300 mA heater, Octal base with triode grid on top cap. Typically, all sections of this tube are arranged around a single heater
  • 6T4 – Low-μ triode used as UHF oscillator, 225 mA heater, Miniature 7-pin base
  • 6T5 – Top-view, "Magic Eye"-type tuning indicator with a remote-cutoff driver triode, 300 mA heater, U6A base; 6G5/6U5 with a ring-shaped indicating area that varies its inner diameter with the signal strength
  • 6T6-GM – RF Pentode, 450 mA heater, Octal base with control grid on top cap
  • 6T7-G – Dual diode + high-μ triode used in pre-war farm radios, 150 mA heater, Octal base with control grid on top cap; similar to 6Q7
  • 6T8, 6T8A – Triple diode + high-μ triode on common cathode with two of the diodes used as AM detector/AVC rectifier/FM ratio detector/AF amplifier in North American AM/FM radios, triode μ = 70, 450 mA heater, Noval base; 6AK8/EABC80 with a shorter glass envelope
  • 6T9Compactron Triode + 12-watts power pentode, 930 mA heater
  • 6T10Compactron Dual-control, sharp-cutoff pentode + 10-watts power pentode used as FM quadrature demodulator and AF power amplifier, 950 mA heater
  • 6TE8-GT – Triode/hexode oscillator/mixer, 300 mA heater, Octal base
  • 6U3/EY80 – CRT horizontal deflection output booster/damper/efficiency diode, 900 mA heater, Noval base
  • 6U4-GT – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, 5-pin Octal base
  • 6U5, 6U5-G – See 6G5/6U5
  • 6U6-GT – 11 W AF Beam power tetrode, 750 mA heater, 7-pin Octal base
  • 6U7-G – See 6D6
  • 6U8/ECF82, 6U8A – VHF Triode/pentode oscillator/mixer also used as audio preamplifier, 450 mA heater, Noval base
  • 6U9/ECF201 – Triode + remote-cutoff pentode used as CRT vertical deflection oscillator or combined sync sep/clipper/amplifier/phase detector, and video-IF amplifier, Decal base; 5U9/LCF201 or 8U9/PCF201 with a 6.3 V/410 mA heater
  • 6U10Compactron 1× High-μ + 2× medium-μ triple triode, 600 mA heater
  • 6V3, 6V3A – CRT horizontal deflection output booster/damper/efficiency diode, 1.75 A heater, Noval base with cathode on top cap
  • 6V4/EZ80 – 1 kV, 2×45 mA Full-wave rectifier, 600 mA heater, Noval base
  • 6V5-GT – 12 W Beam power tetrode, half-indirect 450 mA heater, Octal base
  • 6V6 (Metal envelope), 6V6-G (Shouldered Tube glass envelope), 6V6-GT, 6V6-GTA (Glass Tubular envelope) – 12 W Beam power tetrode used in single-ended Class-A audio output amplifiers of radios and sometimes seen in Class-B audio amplifiers; 5V6 or 12V6 with a 6.3 V/450 mA heater; electrically similar to 6AQ5/EL90; ruggedized version: 6V6S
  • 6V7-G – Dual diode + medium-μ triode, μ = 8.3, 300 mA heater; similar to 6R7-G; type 85 with an Octal base and grid on top cap
  • 6V8 – Upgraded 6T8 triple diode + high-μ triode
  • 6W2 – Subminiature CRT EHT rectifier, anode on top wire, half-indirect 80 mA heater
  • 6W4-GT, 6W4-GTA – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, 5-pin Octal base
  • 6W5-G – Full-wave rectifier, 900 mA heater, 6-pin Octal base
  • 6W6-GT – 10 W Beam power pentode used as CRT vertical deflection amplifier in 1950s monochrome TV receivers or as an audio output tube; 12L6-GT or 25L6-GT or 50L6-GT with a 6.3 V/1.2 A heater
  • 6W7-G – Pentode, 150 mA heater, 7-pin Octal base with control grid on top cap
  • 6X2/EY51 – 17 kV, 3 mA CRT EHT rectifier, half-indirect 90 mA heater, wire-ended
  • 6X4/6BX4/EZ90 = 6Ц4П6C4P (Miniature 7-pin base) and 6X5/EZ35, 6X5-G, 6X5-GT (6-pin Octal base) – 1.25 kV, 2×210 mA Full-wave rectifiers, 600 mA heater; derived from type 84/6Z4; ruggedized versions: 6X4-W, 6X4-WA, 6X4-WS, 6X5-WGT
  • 6X6-G – Tuning indicator, 300 mA heater, Octal base
  • 6X8, 6X8A – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6X9/ECF200 – Triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and audio-IF or video amplifier, 410 mA heater, Decal base
  • 6Y3-G – 5 kV CRT EHT rectifier, half-indirect 700 mA heater, Octal base
  • 6Y5 – Full-wave rectifier, 800 mA heater; similar to type 84/6Z4, but with U6A base with shield on pin 2
  • 6Y6-G, 6Y6-GA, 6Y6-GT – 12.5 W AF Beam power pentode, 1.25 A heater, 7-pin Octal base
  • 6Y7-G – 11.5 W Dual power triode, 600 mA heater; 79 with an Octal base
  • 6Y9/EFL200 – Pentode + 5-watts power pentode used as audio-IF amplifier or combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and CRT cathode driver, 800 mA heater, Decal base
  • 6Y10Compactron Dual-control, sharp-cutoff pentode + 4.8-watts power pentode used as FM quadrature demodulator and AF power amplifier, 830 mA heater
  • 6Z3 – See 1V/6Z3
  • 6Z4 = 84/6Z4 – Full-wave rectifier, 500 mA heater, UY5 base
  • 6Z5 – See 12Z5
  • 6Z7-G – 8 W Dual AF power triode used in Class-B push-pull amplifiers, 300 mA heater, Octal base
  • 6Z10 – See 6J10/6Z10
  • 6AB4/6664/EC92 – High-μ triode, single ECC81/12AT7 system, 150 mA heater, Miniature 7-pin base
  • 6AB5/6N5 – Top-view, "Magic Eye"-type tuning indicator with a sharp-cutoff driver triode, 150 mA heater, U6A base
  • 6AB6-GTriple-Twin AF signal + zero bias power triode internally connected as a cathode follower, 500 mA heater, U6A base; low-power variant of the 6B5 used in car radios
  • 6AB7/1853 – Semiremote-cutoff RF/IF pentode, 450 mA heater, Octal base
  • 6AB8/ECL80 – Triode + 3.5-watts power pentode, 300 mA heater, Noval base
  • 6AB9 – Dual VHF tetrode, 365 mA heater, Decal base
  • 6AC5-G = CV844Zero bias high-μ power triode designed for operation with positive grid bias up to +13 V supplied from a cathode follower driver triode such as 76, 6J5, 6P5, or half a 6AE7, 400 mA heater, Octal base; cf. 295, 2B6, 6AC6, 6B5, 6N6-G Triple-Twin Darlington triodes
  • 6AC6-G, 6AC6-GTTriple-Twin AF signal + zero bias power triode with a common, single anode, internally connected as a cathode follower, 1.1 A heater, Octal base
  • 6AC7 = 1852 – Sharp-cutoff RF pentode used in analog TV receivers, 450 mA heater, Octal base (not to be confused with the 6CA7/EL34)
  • 6AC9Compactron Dual diode + pentode used as IF amplifier and phase detector, 600 mA heater
  • 6AC10Compactron Triple high-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 600 mA heater
  • 6AD4 (5898) – Subminiature high-μ triode, 150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6AD5-G – High-μ triode used as driver for electrostatic CRT deflection plates, 300 mA heater, Octal base
  • 6AD6-G (100 to 150 V target for AC/DC radios), 6AF6-G (250 V target for larger AC radios) – Top-view, driverless "Magic Eye"-type tuning indicators with two independent "pie wedge" shadow indicators on opposite sides of a single circular target, a 150 mA heater and an Octal base
    Both shadows may be used in tandem or may be driven by two different signal sources. Type 6AE6-G is specifically made to drive 6AD6-G and 6AF6-G, but they may also be driven by a sharp-cutoff pentode like a 6J7-G/EF37 (highly sensitive to weak signals) for one shadow and a remote-cutoff pentode like a 6K7/EF39 (reacting only to stronger signals) for the other
  • 6AD7-G – Triode + 8.5-watts power pentode, 850 mA heater, Octal base
  • 6AD8/EBF81 – Common cathode dual diode + remote-cutoff RF/IF/AF pentode, 300 mA heater, Noval base
  • 6AD10, 6AD10ACompactron Dual-control pentode + 10-watts power pentode used as FM quadrature demodulator and AF power amplifier, 1.05 A heater; similar to 6J10/6Z10
  • 6AE5-G, 6AE5-GT – Low-μ triode, 300 mA heater, 6-pin Octal base
  • 6AE6-G – Split-anode driver triode for tuning indicators 6AD6-G and 6AF6-G, 150 mA heater, common cathode, common grid with a high-μ section for one anode and a vari-μ section for the other. The high-μ grid reacts to weak signals while the vari-μ grid reacts only to stronger signals
  • 6AE7-GT – Common-anode, separate cathodes dual triode used as a cathode follower driver for two push-pull zero bias power triodes such as 6AC5, 500 mA heater; cf. 295, 2B6, 6AC6, 6B5, 6N6-G Triple-Twin Darlington triodes
  • 6AE8 – Triode/hexode oscillator/mixer, 300 mA heater, Noval base
  • 6AF3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Noval base with cathode on top cap
  • 6AF4/EC94, 6AF4A/6DZ4 – Medium-μ UHF oscillator triode used in analog TV tuners and set-top converters, 225 mA heater, Miniature 7-pin base
  • 6AF5-G – Triode, 300 mA heater, 6-pin Octal base
  • 6AF7-G – Dual-sensitivity, top-view, "Magic Eye"-type tuning indicator, 300 mA heater, Octal base
  • 6AF9 – Dual dissimilar pentode used as sound IF amplifier or combined sync sep/clipper/amplifier/phase detector or phase inverter/splitter/comparator or gated AGC DC voltage amplifier/keyer/noise inverter, and CRT cathode driver, 850 mA heater, Decal base
  • 6AF11Compactron High-μ triode + medium-μ triode + sharp-cutoff pentode, 1.05 A heater
  • 6AG5/EF96 = 6Ж3П6J3P – 400 MHz Sharp-cutoff VHF pentode, 300 mA heater, Miniature 7-pin base; premium version: 6AG5-WA/6186
  • 6AG6-G – 10 W Power pentode, 1.2 A heater, Octal base
  • 6AG7/6AK7 – 9 W Power pentode used as CRT cathode driver, 650 mA heater, Octal base
  • 6AG9Compactron Medium-μ triode + frame-grid pentode used as gated AGC amplifier/keyer/noise inverter, and video amplifier in analog color TV receivers, 820 mA heater
  • 6AG11Compactron Dual diode + dual high-μ triode, 750 mA heater
  • 6AH4-GT – Medium-μ triode, 750 mA heater, 6-pin Octal base
  • 6AH5-G – 18.5 W Beam power tetrode for early TV use in some Philco receivers, 900 mA heater, Octal base; 6L6-G with a different pinout
  • 6AH6, 6AH6S (external shield tied to cathode) – Wideband, sharp-cutoff IF pentode, 450 mA heater, Miniature 7-pin base; avionics version: 6AH6-WA
  • 6AH7-GT – Dual triode, 300 mA heater, Octal base
  • 6AH9Compactron Medium-μ triode + sharp-cutoff frame-grid pentode used as video amplifier and color blanker in analog color TV receivers, 900 mA heater
  • 6AJ4/EC84 – High-μ triode, 225 mA heater, Noval base
  • 6AJ5 (7755, 414A) – Low (6.3-80 V) anode voltage, sharp-cutoff pentode, 175 mA heater, Miniature 7-pin base
  • 6AJ7 – Pentode, 450 mA heater, Octal base
  • 6AJ8/ECH81 – Triode/remote-cutoff heptode oscillator/mixer, 300 mA heater, Noval base
  • 6AK4/EC70 – 750 mW, 500 MHz Subminiature medium-μ UHF triode, 150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends; ruggedized version: 6K4
  • 6AK5/EF95/6069 = 6Ж1П6J1P – 400 MHz Sharp-cutoff pentode used in old Radiosonde weather balloon transmitters, receiver front ends and contemporary audio equipment, 175 mA heater, Miniature 7-pin base; avionics versions: 6AK5-W/5654/6096/E95F, 6028/408A, CV4010
  • 6AK6 – 2.75 W Power pentode, unusual low-power consumption output tube with 150 mA heater; 6G6-G with a Miniature 7-pin base; ruggedized version: 6AK6S
  • 6AK7 – See 6AG7/6AK7
  • 6AK8/EABC80 – Triple diode + high-μ triode on common cathode with two of the diodes used as AM detector/AVC rectifier/FM ratio detector/AF amplifier in AM/FM radios manufactured outside of North America, 450 mA heater, Noval base, triode μ = 70; 6T8 with a longer glass envelope
  • 6AK9Compactron high-μ triode + medium-μ triode + 10-watts beam power pentode, 1.6 A heater
  • 6AK10Compactron Triple high-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 900 mA heater
  • 6AL3/EY88 = 6Д20П6D20P – 6 kV, 220 mA CRT horizontal deflection output booster/damper/efficiency diode, 1.55 A heater, Noval base with cathode on top cap
  • 6AL5/EAA91 = M-OV/GEC D77 = 6Х2П6H2P – Dual diode with separate cathodes used as detector, also in vacuum tube volt meters; 6H6 with a Miniature 7-pin base; 12AL5/HAA91, UAA91 or 3AL5/XAA91 with a 6.3 V/300 mA heater; avionics versions: 6AL5-W/5726/6097/E91AA
  • 6AL6-G – 18.5 W Beam power tetrode for early TV use, 900 mA heater, Octal base; 6L6-G with a different pinout and anode on top cap
  • 6AL7-GT – Top-view, driverless, triple (independently controllable) bar graph-type tuning/level indicator used in many early AM/FM Hi-Fi radios, 150 mA heater, Octal base
  • 6AL9Compactron High-μ triode + sharp-cutoff pentode, 820 mA heater
  • 6AL11Compactron Dual-control, sharp-cutoff pentode + 10-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 900 mA heater
  • 6AM4 – High-μ UHF triode used as grounded-grid amplifier, 225 mA heater, Noval base
  • 6AM5/EL91 – 4 W Power pentode, 200 mA heater, Miniature 7-pin base
  • 6AM6/EF91 = M-OV/GEC Z77 (M8083) – Sharp-cutoff RF pentode used in receiver front ends and test gear such as VTVMs and TV broadcast modulation monitors, 300 mA heater, Miniature 7-pin base; ruggedized version: 6AM6S
  • 6AM8, 6AM8A – Diode + sharp-cutoff pentode used as video detector and IF amplifier, 450 mA heater, Noval base
  • 6AN4 – High-μ triode used as UHF mixer or amplifier, 225 mA heater, Miniature 7-pin base
  • 6AN5 – Sharp-cutoff RF/video pentode, Silicon-free 450 mA heater, Miniature 7-pin base; ruggedized version: 6AN5-WA
  • 6AN6 – Common cathode quad diode, 200 mA heater, Miniature 7-pin base
  • 6AN7/ECH80, 6AN7ATriode/remote-cutoff hexode oscillator/mixer, 300 mA heater; 6CU7/ECH42 with a Noval base
  • 6AN8, 6AN8A – Triode + pentode used as combined sync sep/clipper/amplifier/phase detector or phase inverter/splitter/comparator or gated AGC amplifier/keyer/noise inverter, and reactance tube or IF amplifier, 450 mA heater, Noval base
  • 6AQ4/EC91 – 250 MHz VHF triode, 300 mA heater, Miniature 7-pin base
  • 6AQ5/EL90, 6AQ5A/6669 (12 W, tolerant to vehicle heater voltage fluctuations), 6BM5 (9 W), 6HG5 (12 W), 6HR5 – Beam power pentodes used as CRT vertical deflection or audio power amplifier, 450 mA heater; 6CM6 = 6П1П6P1P with a Miniature 7-pin base; similar to 6V6; ruggedized versions: 6AQ5L/6928 (long life), 6AQ5-W/6005
  • 6AQ6 – Dual diode + high-μ AF triode, 150 mA heater, Miniature 7-pin base
  • 6AQ7-GT – Dual diode + high-μ triode, 300 mA heater, Octal base
  • 6AQ8/ECC85 – 200 MHz Dual RF/VHF triode used as oscillator/mixer (the heater to cathode insulation is inadequate for use in cascode operation) in FM receivers, separate cathodes, internal shield between the two sections, 435 mA heater, Noval base; similar to 6BK7, 6BQ7, 6BZ7
  • 6AR5 – 8.5 W Power pentode, 400 mA heater, Miniature 7-pin base
  • 6AR6 – 19 W Beam power pentode, 1.2 A heater, 6-pin Octal base; avionics versions: 6AR6-WA/6098, 6384
  • 6AR7-GT – Dual diode + remote-cutoff pentode, 300 mA heater, Octal base
  • 6AR8, 6HW8, 6JH8, 6ME8 – Sheet-beam deflection tubes used as NTSC chroma signal demodulators in analog color TV receivers, 300 mA heater, Noval base
  • 6AR11Compactron Semiremote-cutoff dual IF pentode, 800 mA heater
  • 6AS5 – 5.5 W AF Beam power pentode, 800 mA heater, Miniature 7-pin base
  • 6AS6 = Western Electric 409A = 6Ж2П6J2P – Dual-control pentode used e.g. in radar phantastron circuits, 175 mA heater, Miniature 7-pin base; similar to EF80; avionics version: 6AS6-W/5725/6187
  • 6AS7 = 6Н5С6N5S, 6AS7-G/ECC230 = 6Н13С6N13S (6080), 6AS7-GYB (Micanol base) – 13 W Dual low impedance, low-μ triode designed as series-pass regulator in stabilized DC power supplies, 2.5 A heater, Octal base
  • 6AS8 – High-perveance diode + sharp-cutoff pentode used as audio/video detector or gated AGC amplifier/keyer/noise inverter or DC restorer and IF or video amplifier, 450 mA heater, Noval base
  • 6AS11Compactron High-μ triode + medium-μ triode + sharp-cutoff pentode, 1.05 A heater
  • 6AT6/EBC90 – Common cathode dual diode + high-μ AF triode used in FM ratio detectors, triode μ = 70, 300 mA heater; 6Q7 with a Miniature 7-pin base
  • 6AT8, 6AT8A – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6AU4-GT, 6AU4-GTA – 4.5 kV, 1.1 A CRT horizontal deflection output booster/damper/efficiency diode, 1.8 A heater, 6-pin Octal base
  • 6AU5-GT – 10 W Beam power tetrode, 1.25 A heater, 6-pin Octal base
  • 6AU6/EF94, 6AU6A = 6Ж4П6J4P – Sharp-cutoff pentode, 300 mA heater, Miniature 7-pin base; avionics versions: 6AU6-WA, 6AU6-WB
  • 6AU8, 6AU8A – Medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector and IF or video amplifier, 600 mA heater, Noval base
  • 6AV4/EZ91 – 1 kV, 2×45 mA Full-wave rectifier, 950 mA heater, Miniature 7-pin base
  • 6AV5-GA, 6AV5-GT – 11 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, Octal base
  • 6AV6/EBC91 – Common cathode dual diode + high-μ AF triode used in FM ratio detectors, triode μ = 100 (triode section similar in characteristics to one half of a 12AX7/ECC83), 300 mA heater; type 75 with a Miniature 7-pin base
  • 6AV11Compactron Triple medium-μ triode, 600 mA heater
  • 6AW7-GT – Dual diode + triode, 300 mA heater, Octal base
  • 6AW8, 6AW8A – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector and video amplifier, 600 mA heater, Noval base
  • 6AX3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater
  • 6AX4, 6AX4-GTA, 6AX4-GTB – 4.4 kV, 137 mA CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, 6-pin Octal base
  • 6AX5 – 1.25 kV, 2×375 mA Full-wave rectifier, 1.2 A heater, Octal base; similar in structure to 6X5, but with higher voltage and current ratings which are comparable to those of 5Y3 and 80
  • 6AX6-G – Dual rectifier with separate cathodes, 2.5 A heater, 7-pin Octal base
  • 6AX8 – Medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector and video amplifier, 450 mA heater, Noval base
  • 6AY3, 6AY3A, 6AY3B – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Novar base
  • 6AY11Compactron Dual diode + dual high-μ triode used as FM demodulator and AF amplifier, 690 mA heater
  • 6AZ5 – Subminiature dual diode, separate cathodes, 150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6AZ6 – Subminiature, ruggedized, dual UHF diode with separate cathodes, 150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6AZ8 – Medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or phase inverter/splitter/comparator or gated AGC amplifier/keyer/noise inverter and IF or video amplifier, 450 mA heater, Noval base
  • 6BA3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Novar base
  • 6BA4Rocket-type, coaxial, disk-seal UHF planar triode, 375-425 mA heater
  • 6BA5 – Subminiature, sharp-cutoff pentode, 150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6BA6/EF93 = M-OV/GEC W727 = 6К4П6K4P – Remote-cutoff RF pentode, 300 mA heater, popular in car radios; avionics version: 6BA6-W/5749
  • 6BA7 – See 6SB7Y
  • 6BA8, 6BA8A – Medium-μ triode + sharp-cutoff pentode with controlled anode knee characteristic, used as combined sync sep/clipper/amplifier/phase detector and video amplifier, 600 mA heater, Noval base
  • 6BA11Compactron Triode + split-anode pentode used as CRT vertical deflection oscillator and combined sync sep/clipper/amplifier/phase detector, 600 mA heater
  • 6BC4 – Medium-μ RF triode, 225 mA heater, Noval base
  • 6BC5/6CE5 – 400 MHz Semiremote-cutoff VHF pentode, 300 mA heater, Miniature 7-pin base; 6AG5/EF96 with a higher μ
  • 6BC7 – Separate cathodes triple diode, 450 mA heater, Noval base
  • 6BC8 – Dual semiremote-cutoff VHF triode used as cascode amplifier, 400 mA heater, Noval base
  • 6BD4 (20 kV, 20 W), 6BD4A (27 kV, 25 W) – 1.5 mA Beam power triode used as EHV shunt regulator in analog color TV receivers, 500 mA heater, 6-pin Octal base with anode on top cap
  • 6BD5-GT – 10 W Beam power pentode used as CRT horizontal deflection amplifier, 900 mA heater, 6-pin Octal base
  • 6BD6 – Remote-cutoff RF/IF pentode, 300 mA heater, Miniature 7-pin base
  • 6BD7/EBC80 – Shielded dual diode + AF triode, 230 mA heater, Noval base
  • 6BD11Compactron High-μ triode + medium-μ triode + sharp-cutoff pentode, 1.05 A heater
  • 6BE3/6BZ3, 6BE3ACompactron CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater
  • 6BE6/EK90 = M-OV/GEC X727 = 6А2П6A2P (5750) – Remote-cutoff heptode pentagrid converter with American grid topology, 300 mA heater, Miniature 7-pin base, popular in car radios
  • 6BE7/EQ80Nonode for FM quadrature demodulation, 200 mA heater, Noval base
  • 6BE8, 6BE8A – VHF Medium-μ triode/sharp-cutoff pentode oscillator/mixer, 450 mA heater, Noval base
  • 6BF5 – 5.5 W Beam power tetrode, 1.2 A heater, Miniature 7-pin base
  • 6BF6 – Dual diode + medium-μ triode, 300 mA heater; 6R7 with a Miniature 7-pin base
  • 6BF7, 6BF7A – Subminiature, separate cathodes dual triode, 300 mA heater, all-glass round cross-section envelope with 8 long inline wire-ends; similar to 6J6/ECC91
  • 6BF8 – Sextuple diode with a common cathode, 450 mA heater, Noval base
  • 6BF11Compactron Dual-control, sharp-cutoff pentode + 6.5-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 1.2 A heater
  • 6BG6 (ST envelope), 6BG6-GA (GT) – 20 W Beam power pentode used in early TV magnetic-deflection horizontal-output amplifiers, 900 mA heater, Octal base; 6L6-G with the anode on top cap
  • 6BG7 – Subminiature dual triode, 300 mA heater, all-glass envelope, 8-pin/wire-ends
  • 6BH3, 6BH3A – CRT horizontal deflection output booster/damper/efficiency diode, 1.6 A heater, Novar base
  • 6BH5/EF81 – Remote-cutoff RF/IF/video pentode, 200 mA heater, Noval base
  • 6BH6 (7693/E90F, 6265) – Sharp-cutoff RF pentode, 150 mA heater, Miniature 7-pin base
  • 6BH8 – Medium-μ triode + sharp-cutoff pentode used as CRT vertical deflection oscillator or combined sync sep/clipper/amplifier/phase detector, and IF or video amplifier, 600 mA heater, Noval base; 6AU8 with a lower-μ triode
  • 6BH11Compactron Dual medium-μ triode + sharp-cutoff pentode, 800 mA heater
  • 6BJ3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater
  • 6BJ5 – 9 W Power pentode, 200 mA heater, Miniature 7-pin base
  • 6BJ6, 6BJ6A – Remote-cutoff RF/IF pentode, 150 mA heater, Miniature 7-pin base
  • 6BJ7 – Triple diode used as DC restorer in analog color TV receivers, 450 mA heater, Noval base
  • 6BJ8 – Dual diode + medium-μ triode used as phase inverter/splitter/comparator and CRT vertical deflection amplifier, 600 mA heater, Noval base
  • 6BK4 = 6С20С6S20S – 27 kV, 25 W, 1.5 mA Beam power triode used as EHV shunt regulator in analog color TV receivers and in measurement equipment such as high voltage meters, 200 mA heater, Uh-c=-200 V, Octal base with anode on top cap
  • 6BK5 – 9 W Beam power pentode, 1.2 A heater, Noval base
  • 6BK6 – Common cathode dual diode + high-μ AF triode used as detector and AF amplifier, Miniature 7-pin base; 12BK6 or 26BK6 with a 6.3 V/300 mA heater
  • 6BK7, 6BK7A, 6BK7B – Dual RF/VHF triode with separate cathodes and an internal shield between the two sections, 450 mA heater; similar to 6AQ8/ECC85, 6BQ7, 6BZ7
  • 6BK8/6CF8/EF86 = M-OV/GEC Z729 – AF Pentode used in microphone preamplifiers and audiophile gear, 200 mA heater
  • 6BK11Compactron 2× High-μ + 1× medium-μ triple triode used as preamplifier in some guitar amps made by Ampeg, 600 mA heater
  • 6BL4 – CRT horizontal deflection output booster/damper/efficiency diode, 3 A heater, Octal base
  • 6BL6 – 250 mW, 1.6-6.5 GHz Reflex Klystron, 750 mA heater, 4-pin PeeWee base with external-cavity contact rings and top cap; CW-only variant of 5836
  • 6BL7-GT, 6BL7-GTA – Dual triode used as CRT vertical deflection oscillator+amplifier, 1.5 A heater, Octal base
  • 6BL8/ECF80 = 6Ф1П6F1P – General-purpose triode + pentode used in analog TV receivers, audio and test gear, 450 mA heater, Noval base
  • 6BM5 – See 6AQ5/EL90
  • 6BM6 – 150 mW, 0.55-3.8 GHz Reflex Klystron, 650 mA heater, 4-pin PeeWee base with external-cavity contact rings and top cap; CW-only variant of 6BM6A/5837
  • 6BM8/ECL82 = 6Ф3П6F3P – Triode + pentode used as CRT vertical deflection or AF amplifier and has even been seen in an electronic nerve stimulator, 780 mA heater, Noval base
  • 6BN4, 6BN4A – Medium-μ VHF triode, 200 mA heater, Miniature 7-pin base
  • 6BN5/EL85 – 6 W, 120 MHz RF/AF power pentode, 200 mA heater, Noval base
  • 6BN6/6KS6 = 6А3П6A3PGated-beam discriminator pentode used in radar, dual channel oscilloscopes and FM quadrature demodulators where the suppressor grid is connected to ground via an LC tank circuit tuned for a 90° phase lag to the IF at center frequency, Miniature 7-pin base;[114][115] precursor of the Nonode approach; 3BN6, 4BN6, 12BN6 with a 6.3 V/300 mA heater
  • 6BN7 – Dual triode used as CRT vertical deflection oscillator+amplifier, 750 mA heater, Noval base
  • 6BN8 – Dual diode + high-μ triode used as phase/ratio discriminator, AF/burst amplifier or oscillator, 600 mA heater, Noval base
  • 6BN11Compactron Dual sharp-cutoff IF pentode, 800 mA heater
  • 6BQ5/EL84 = M-OV/GEC N709 = 6П14П6P14P – 5.7 Watts AF power pentode, 760 mA heater, Noval base
  • 6BQ6-G, 6BQ6-GA, 6BQ6-GT – 12 W Beam power pentode used as a horizontal deflection output tube in 1950s monochrome TV receivers with diagonal screen sizes less than 19 in (48 cm), however, may be found in some larger models which more often used similar type 6DQ6, 1.2 A heater, Octal base
  • 6BQ6-GTB/6CU6 – Upgraded 6BQ6-GT
  • 6BQ7 – Dual RF/VHF triode with separate cathodes and an internal shield between the two sections, which can be used independently or in a cascode amplifier, 400 mA heater, Noval base; similar to 6AQ8/ECC85, 6BK7, 6BZ7
  • 6BQ7A/ECC180 – Upgraded 6BQ7 capable of operation at UHF frequencies; similar to 6Н1П6N1P
  • 6BR3 = 6RK19 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Noval base
  • 6BR5/EM80 – Side-view, fan-type tuning indicator, 300 mA heater, Noval base
  • 6BR7 (Control grid on base), 6BS7 (control grid on top cap) – Low-hum, low-microphonics AF pentode, 150 mA heater, Noval base
  • 6BR8/6FV8, 6BR8A/6FV8A – Medium-μ triode + sharp-cutoff pentode used as CRT vertical deflection oscillator and IF amplifier, 450 mA heater, Noval base
  • 6BS3, 6BS3A – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Novar base
  • 6BS5 – 12.5 W Beam power tetrode used as AF or CRT cathode driver, or CRT vertical deflection amplifier, 750 mA heater, Noval base
  • 6BS7 – See 6BR7
  • 6BS8 – Medium-μ dual VHF triode used as cascode amplifier, 400 mA heater, Noval base
  • 6BT4/EZ40 – 780 V, 2×45 mA Full-wave rectifier, 600 mA heater, Rimlock base
  • 6BT6 – Dual diode + high-μ triode, 300 mA heater, Miniature 7-pin base
  • 6BT8 – Dual diode + sharp-cutoff pentode used as gated AGC amplifier/keyer/noise inverter, or IF or video amplifier/detector, 450 mA heater, Noval base
  • 6BU4 – 25 kV, 25 W, 1 mA Beam power triode used as EHV shunt regulator in analog color TV receivers, 450 mA heater, Octal base with anode on top cap
  • 6BU5 – 20 kV, 20 W, 1 mA Beam power pentode used as EHV shunt regulator in analog color TV receivers, 150 mA heater, Octal base with anode on top cap
  • 6BU6 – Dual diode + triode, 300 mA heater, Miniature 7-pin base
  • 6BU8/6GS8, 6BU8A, 6HS8, 6LE8, 6MK8 – Split-anode pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, 300 mA heater, Noval base
  • 6BV7 – Dual diode + 10-watts power pentode, 800 mA heater, Noval base
  • 6BV8 – Dual diode + triode, 600 mA heater, Noval base
  • 6BV11Compactron Dual sharp-cutoff dual-dontrol pentode used as color demodulator, 900 mA heater
  • 6BW3/6CG3/6DQ3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 1.6 A heater
  • 6BW4 – 1.275 kV, 2×350 mA Full-wave rectifier, 900 mA heater, Noval base
  • 6BW6 – 13.2 W Beam power tetrode, 450 mA heater, Noval base
  • 6BW7 – RF Pentode, 300 mA heater, Noval base
  • 6BW8 – Dual diode + sharp-cutoff pentode, 450 mA heater, Noval base
  • 6BW11Compactron Dual dissimilar pentode used as medium-gm video amplifier, and high-gm bandpass or color burst or IF amplifier, 800 mA heater
  • 6BX4 – See 6X4/6BX4/EZ90
  • 6BX6/EF80 – Sharp-cutoff RF/IF/video pentode, 300 mA heater, Noval base
  • 6BX7-GT – Dual triode used as CRT vertical deflection oscillator+amplifier, 1.5 A heater, Octal base
  • 6BX8 – Dual VHF triode used as cascode amplifier, 400 mA heater, Noval base
  • 6BY4 – Miniature, ceramic/metal, disk-seal, coaxial UHF planar triode, 250 mA heater
  • 6BY5-G, 6BY5-GA – Dual CRT horizontal deflection output booster/damper/efficiency diode with separate cathodes, 1.6 A heater, 7-pin Octal base
  • 6BY6 – Similar to 6CS6/EH90, but with higher transconductance, Miniature 7-pin base; 3BY6 with a 6.3 V/300 mA heater
  • 6BY7/EF85 = M-OV/GEC W719 – Remote-cutoff RF pentode, 300 mA heater, Noval base
  • 6BY8 – High perveance diode + sharp-cutoff pentode used as limiter or detector and RF/IF amplifier, 600 mA heater, Noval base
  • 6BY11Compactron Dual-control pentode + 10-watts power pentode used as FM quadrature demodulator and AF power amplifier, 1.2 A heater
  • 6BZ3 – See 6BE3/6BZ3
  • 6BZ6 – Sharp-cutoff RF pentode used in 1960s video-IF circuits, 300 mA heater, Miniature 7-pin base
  • 6BZ7 – Dual RF/VHF triode with separate cathodes and an internal shield between the two sections, 400 mA heater, Noval base; similar to 6AQ8/ECC85, 6BK7, 6BQ7
  • 6BZ8 – Dual medium-μ VHF triode, 400 mA heater, Noval base
  • 6CA4/EZ81 – 1 kV, 2×450 mA Full-wave rectifier, 1 A heater, Noval base
  • 6CA7/EL34 = 6П27С6P27S – 25 W AF power pentode, 1.5 A heater, Octal base
  • 6CA11Compactron Dual high-μ triode + frame-grid, sharp-cutoff video pentode, 1.02 A heater
  • 6CB5 (ST envelope, 23 W), 6CB5A (GT, 26 W) – Beam power pentode used as CRT horizontal deflection amplifier, 2.5 A heater, Octal base
  • 6CB6, 6CB6A/6CF6/6676/EF190 – Sharp-cutoff RF pentode used in 1950s and early 1960s video-IF circuits, 300 mA heater, Miniature 7-pin base
  • 6CD3/6CE3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 2.5 A heater
  • 6CD6-G (ST envelope, 15 W), 6CD6-GA (GT, 20 W) – Beam power pentode used as CRT horizontal deflection amplifier, 2.5 A heater, Octal base with anode on top cap
  • 6CD7/EM34 – Dual-sensitivity, top-view, "Magic Eye"-type tuning indicator, 200 mA heater, Octal base
  • 6CE5 – See 6BC5/6CE5
  • 6CF6 – See 6CB6
  • 6CF8 – See 6BK8/6CF8/EF86
  • 6CG3 – See 6BW3/6CG3/6DQ3
  • 6CG6 – Remote-cutoff pentode, 300 mA heater, Miniature 7-pin base
  • 6CG7/6FQ7 (7026) – Dual triode used in analog TV receivers and some audio amplifiers including modern solid-state designs, often as a cathode follower, 600 mA heater; 6SN7 with a Noval base
  • 6CG8, 6CG8A – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6CH3/6CJ3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.8 A heater, Novar base
  • 6CH6/EL821 (6132) – 12 W Power pentode used as CRT cathode driver in high definition television equipment, 750 mA heater, Noval base
  • 6CH7 – Medium-μ dual RF triode used as cascode amplifier, 400 mA heater, Noval base
  • 6CH8 – Medium-μ triode + sharp-cutoff pentode, 450 mA heater, Noval base
  • 6CJ3 – See 6CH3
  • 6CJ5/EF41 – Remote-cutoff RF/IF pentode, 200 mA heater, Rimlock base
  • 6CJ6/EL81 – 8 W Power pentode used as CRT horizontal deflection amplifier, 1.05 A heater, Noval base
  • 6CK3/6CL3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Novar base
  • 6CK4 – Low-μ triode used as CRT vertical deflection amplifier, 1.25 A heater, 6-pin Octal base
  • 6CK5/EL41 – 9 W AF Power pentode, 700 mA heater, Rimlock base
  • 6CK6/EL83 – 9 W Power pentode used as CRT cathode driver, 710 mA heater, Noval base
  • 6CL3 – See 6CK3
  • 6CL6 – 7.5 W Power pentode used as CRT cathode driver, 650 mA heater, Noval base
  • 6CL8, 6CL8A – Medium-μ triode + sharp-cutoff VHF tetrode used as oscillator/mixer, 450 mA heater, Noval base
  • 6CM3 – CRT horizontal deflection output booster/damper/efficiency diode, 2.4 A heater, Novar base
  • 6CM4/EC86 – UHF triode, Noval base; 4CM4/PC86 with a 6.3 V/170 mA heater
  • 6CM5/EL36 = 6П31С6P31S – 10 W Beam power tetrode used as AF or CRT horizontal deflection amplifier, 1.25 A heater, Octal base
  • 6CM6 = 6П1П6P1P6AQ5/EL90 with a Noval base
  • 6CM7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 600 mA heater, Noval base
  • 6CM8 – High-μ triode + sharp-cutoff pentode, 450 mA heater, Noval base
  • 6CN6/EL38 – 25 W Power pentode used as CRT horizontal deflection amplifier, 1.4 A heater, Octal base
  • 6CQ4/6DE4 – CRT horizontal deflection output booster/damper/efficiency diode, 1.6 A heater, Octal base
  • 6CQ6/EF92 (6CQ6S) – Remote-cutoff RF pentode, 200 mA heater, Miniature 7-pin base
  • 6CQ8 – Medium-μ triode + sharp-cutoff tetrode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6CR4 = M-OV/GEC A2521grounded-grid UHF triode used as cascode amplifier, 370 mA heater, Noval base
  • 6CR5 – 11 W Beam power tetrode used as CRT horizontal deflection amplifier, 1.2 A heater, Noval base
  • 6CR6 – Diode + remote-cutoff pentode, 300 mA heater, Miniature 7-pin base
  • 6CR8, 6CS8 (Different pinout) – Triode + IF pentode, 450 mA heater, Noval base
  • 6CS5 – 11 W AF Beam power pentode, 1.2 A heater, Noval base; similar to 6W6-GT
  • 6CS6/EH90 – Sharp-cutoff heptode with American grid topology, used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, 300 mA heater, Miniature 7-pin base
  • 6CS7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, or in tube audio amplifiers, 600 mA heater, Noval base
  • 6CT3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Noval base
  • 6CT7/EAF42 – Diode + remote-cutoff RF/IF/AF pentode, 200 mA heater, Rimlock base
  • 6CU5 – 7 W AF Beam power pentode, 1.2 A heater, Miniature 7-pin base
  • 6CU6 – See 6BQ6-GT
  • 6CU7/ECH42 – Triode/remote-cutoff hexode oscillator/mixer, 230 mA heater, Rimlock base
  • 6CU8 – Medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and IF or video amplifier, 450 mA heater, Noval base
  • 6CV7/EBC41 – Shielded common cathode dual diode + AF triode, 230 mA heater, Rimlock base
  • 6CW5/EL86 – 12 W AF Beam power pentode, 760 mA heater, Noval base
  • 6CX7 – Medium-μ dual triode, 400 mA heater, Noval base
  • 6CX8 – Medium-μ triode + sharp-cutoff pentode used as CRT deflection oscillator or amplifier and video amplifier, 750 mA heater, Noval base
  • 6CY5/7717 (6CY5/CATV) – Sharp-cutoff VHF tetrode, 200 mA heater, Miniature 7-pin base
  • 6CY7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 750 mA heater, Noval base
  • 6CW4Nuvistor High-μ VHF triode, 135 mA heater, most common one in consumer electronics
  • 6CZ5 (6973) – 10 W Beam power pentode used as CRT vertical deflection or audio amplifier, 450 mA heater, Noval base
  • 6DA4/6DM4, 6DA4A/6DM4A – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, 5-pin Octal base
  • 6DA5/EM81 – Tuning indicator, 300 mA heater, Noval base; 6BR5/EM80 with 25% greater sensitivity
  • 6DA6/EF89 – RF Pentode used in AM/FM radios manufactured outside North America, 200 mA heater, Noval base
  • 6DA7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 1 A heater, Noval base
  • 6DB5 – 10 W Beam power tetrode, 1.2 A heater, Noval base
  • 6DC6 – Semiremote-cutoff pentode, 300 mA heater, Miniature 7-pin base
  • 6DC8/EBF89 – Common cathode dual diode + semiremote-cutoff RF/IF pentode, 300 mA heater, Noval base
  • 6DE4 – See 6CQ4/6DE4
  • 6DE6 – Sharp-cutoff IF pentode, 300 mA heater, Miniature 7-pin base
  • 6DE7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 900 mA heater, Noval base
  • 6DG6-GT – 10 W AF Beam power pentode, 1.2 A heater, Octal base
  • 6DG7 – Remote-cutoff RF/IF pentode, 300 mA heater, Noval base
  • 6DH7/6FG6/EM84 = 6Е3П6Ye3P – Side-view, band-type tuning/level indicator, 270 mA heater, Noval base
  • 6DJ8/ECC88 = 6Н23П6N23P = Shuguang 6N11 (6Н11) – Dual VHF triode used as cascode amplifier in TV broadcast equipment, test gear, oscilloscopes and audiophile gear, 365 mA heater, Noval base; similar to 6ES8/ECC189, 6922/E88CC
  • 6DK3 – CRT horizontal deflection output booster/damper/efficiency diode, 1.8 A heater, Novar base with cathode on top cap
  • 6DK6 – Sharp-cutoff IF pentode, 300 mA heater, Miniature 7-pin base
  • 6DL3 – CRT horizontal deflection output booster/damper/efficiency diode, 2.3 A heater, Novar base with cathode on top cap
  • 6DL5/EL95 – 6 W AF Power pentode used in car radios, 200 mA heater, Miniature 7-pin base
  • 6DL7 – Tuning indicator, 300 mA heater, Octal base
  • 6DM4, 6DM4A – See 6DA4/6DM4
  • 6DN3 – CRT horizontal deflection output booster/damper/efficiency diode, 2.4 A heater, Novar base
  • 6DN6 – 15 W Beam power tetrode used as CRT horizontal deflection amplifier, 2.5 A heater, 6-pin Octal base
  • 6DN7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 900 mA heater, Octal base
  • 6DQ3 – See 6BW3/6CG3/6DQ3
  • 6DQ4 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, 5-pin Octal base
  • 6DQ5 – 24 W Beam power pentode used as CRT horizontal deflection amplifier, 2.5 A heater, Octal base
  • 6DQ6A – 18 W Beam power pentode used as a horizontal deflection output tube in 1950s monochrome TV receivers, mostly those with diagonal screen sizes larger than 17 in (43 cm), 1.2 A heater, Octal base. Smaller receivers often used similar type 6BQ6-GT. Also used as audio output tubes in Standel guitar amplifiers
  • 6DQ6B/6GW6 – 6DQ6 with higher ratings and a higher zero-bias anode current
  • 6DR4 – High-μ triode, 150 mA heater, Miniature 7-pin base; similar to one section of 12AX7/ECC83
  • 6DR6 – 8 W Power pentode, 1.05 A heater, Noval base
  • 6DR7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 900 mA heater, Noval base
  • 6DR8/EBF83 – Common cathode dual diode + low (6.3-50 V) anode voltage pentode used as IF amplifier, detector and AGC diode in vehicle equipment, 300 mA heater, Noval base
  • 6DS4Nuvistor Semiremote-cutoff VHF triode used in analog TV tuners immediately prior to the introduction of solid state tuning circuits (RCA TV receivers equipped with a 6DS4 tuner bore the trademark "Nu-Vista Vision"), 135 mA heater; successor of type 6CW4
  • 6DS5 – 9 W AF Beam power pentode, 800 mA heater, Miniature 7-pin base
  • 6DS8/ECH83 – Low (6.3-25 V) anode voltage, triode/sharp-cutoff heptode oscillator/mixer used in vehicle equipment, 300 mA heater, Noval base
  • 6DT3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 2.4 A heater
  • 6DT4 – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, 6-pin Octal base
  • 6DT5 – 9 W Beam power tetrode used as CRT vertical deflection amplifier, Noval base; 12DT5 or 25DT5 with a 6.3 V/1.2 A heater
  • 6DT6, 6DT6A – Dual-control pentode used in FM quadrature demodulators; 3DT6, 4DT6, 12DT6 with a 6.3 V/300 mA heater
  • 6DT8 – High-μ dual triode used as RF amplifier or oscillator/mixer, 300 mA heater, Noval base
  • 6DU3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 2.1 A heater
  • 6DV4 – Medium-μ Nuvistor triode for UHF oscillators, 135 mA heater; some variants had a Gold-plated envelope
  • 6DW4, 6DW4A, 6DW4B – CRT horizontal deflection output booster/damper/efficiency diode, 1.2 A heater, Novar base
  • 6DW5 – 11 W Power pentode used as CRT vertical deflection amplifier, 1.2 A heater, Noval base
  • 6DX4 – UHF triode, 200 mA heater, Miniature 7-pin base
  • 6DX8/ECL84 = 6Ф4П6F4P – Triode + 4-watts power pentode used as combined sync sep/clipper/amplifier/phase detector, and CRT cathode driver, 720 mA heater, Noval base
  • 6DY4, 6DY4A – UHF frame-grid triode, 125 mA heater, Miniature 7-pin base
  • 6DY5/EL82 – 9 W Power pentode used as CRT vertical deflection or AF amplifier, 800 mA heater, Noval base
  • 6DY7 – 2×15 W Dual AF beam power pentode used in Stereo amplifiers, 1.2 A heater, Octal base
  • 6DZ4/6AF4A – See 6AF4/EC94
  • 6DZ7 – 2×13.2 W Dual AF power pentode used in Hi-Fi Stereo amplifiers, 1.52 A heater, Octal base
  • 6DZ8 – High-μ AF triode + 6.5-watts AF power pentode, 900 mA heater, Noval base
  • 6EA4 – 27 kV, 30 W, 1.6 mA Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, anode on top cap
  • 6EA5 – Sharp-cutoff tetrode, 200 mA heater, Miniature 7-pin base
  • 6EA7 (6EM7) – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 1.05 A heater, Octal base
  • 6EA8 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6EB5 – Dual diode, 300 mA heater, Miniature 7-pin base
  • 6EB8/6GN8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 750 mA heater, Noval base
  • 6EC4/EY500 – CRT horizontal deflection output booster/damper/efficiency diode for analog color TV receivers, Magnoval base with cathode on top cap, guardian shield between filament and cathode to improve high voltage properties; 42EC4/PY500 with a 6.3 V/2.1 A heater
  • 6EC4A/EY500A – 6EC4/EY500 without the guardian shield because of an improved filament/cathode insulation
  • 6EC7 – Remote-cutoff RF pentode, 200 mA heater, Noval base
  • 6EF4Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, anode on top cap
  • 6EF6 – 10 W Compactron Beam power pentode used as CRT vertical deflection amplifier, 200 mA heater
  • 6EH4A – 27 kV, 40 W, 1.5 mA Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, anode on top cap
  • 6EH5 – 5.5 W AF Beam power pentode, 1.2 A heater, Miniature 7-pin base
  • 6EH7/EF183 – Frame-grid, remote-cutoff IF pentode, 300 mA heater, Noval base
  • 6EH8 – Triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6EJ4A – 27 kV, 40 W, 1.5 mA Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, anode on top cap
  • 6EJ7/EF184 – Frame-grid, sharp-cutoff IF pentode, 300 mA heater, Noval base
  • 6EL4A – See 6BK4C/6EL4A
  • 6EL7 = EdiSwan 6F23 – Screened RF pentode, 300 mA heater, Noval base
  • 6EM5 – 10 W Power pentode used as CRT vertical deflection amplifier, 800 mA heater, Noval base
  • 6EM7 (6EA7) – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 925 mA heater, Octal base
  • 6EN4 – 30 kV, 40 W, 1.6 mA Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, Octal base with anode on top cap
  • 6EQ7 – Diode + sharp-cutoff IF pentode used as detector and IF amplifier, 300 mA heater, Noval base
  • 6ER5 – VHF tubes, 6.3 V/180 mA heater, Miniature 7-pin base:
  • 6ER5/EC95 (Tung-Sol, Sylvania, Philips) – Vari-μ triode[116]; 2ER5/XC95 or 4ER5/PC95 with a different heater
  • 6ER5 (RCA) – High-μ triode[117]
  • 6ER5 (Tung-Sol) – Remote-cutoff tetrode[118]
  • 6ES5 – High-μ VHF triode, 200 mA heater, Miniature 7-pin base
  • 6ES6/EF97 = 6К8П6K8P (remote-cutoff), 6ET6/EF98 (sharp-cutoff) – Low (6.3-50 V) anode voltage RF pentodes used in car radios, 300 mA heater, Miniature 7-pin base
  • 6ES8/ECC189 – Dual VHF triode used as cascode amplifier in analog TV tuners and receiver front ends, also used as general-purpose dual triode in test gear, 365 mA heater, Noval base; similar to 6DJ8/ECC88
  • 6ET6/EF98 – Low (6.3-50 V) anode voltage, sharp-cutoff pentode used as oscillator or IF/AF amplifier in vehicle equipment, 300 mA heater, Miniature 7-pin base
  • 6ET7 – Dual diode + sharp-cutoff pentode used as horizontal phase detector and video amplifier, 750 mA heater, Noval base
  • 6EU7 – High-μ dual triode used as AF amplifier or phase inverter, 300 mA heater, Noval base
  • 6EU8 – Medium-μ triode + sharp-cutoff pentode used as oscillator/mixer, 450 mA heater, Noval base
  • 6EV5 – Sharp-cutoff VHF tetrode, 200 mA heater, Miniature 7-pin base
  • 6EV7 – Dual triode, 600 mA heater, Noval base
  • 6EW6 – Sharp-cutoff IF pentode, 400 mA heater, Miniature 7-pin base
  • 6EW7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 900 mA heater, Noval base
  • 6EX6 – 22 W Beam power tetrode used as CRT horizontal deflection amplifier, 2.25 A heater, 6-pin Octal base
  • 6EY6 – 11 W Beam power pentode used as CRT vertical deflection amplifier, 680 mA heater, 6-pin Octal base
  • 6EZ5 – 12 W Beam power pentode used as CRT vertical deflection amplifier, 800 mA heater, Octal base
  • 6EZ8 – Triple high-μ VHF triode used in FM tuners, 450 mA heater, Noval base, cathodes 1 and 2 and one side of the heater share pin 4
  • 6FA7 – Diode + sharp-cutoff split-anode tetrode used as frequency divider or complex-wave generator, 300 mA heater, Noval base
  • 6FC7/ECC89 – 220 MHz Dual frame-grid VHF triode used as cascode amplifier in analog TV tuners and receiver front ends, or as general-purpose instrumentation amplifier, 340 mA heater, Noval base
  • 6FD7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 925 mA heater, Noval base
  • 6FG5, 6FS5, 6GU5Shadow-grid Sharp-cutoff VHF beam pentodes, 200 mA heater, Miniature 7-pin base
  • 6FG6 – See 6DH7/6FG6/EM84
  • 6FG7 – Medium-μ triode + semiremote-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6FH5 – High-μ VHF triode, 200 mA heater, Miniature 7-pin base
  • 6FH6 – 17 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, 7-pin Octal base
  • 6FH8 – Medium-μ triode + triple-anode sharp-cutoff tetrode used in harmonic-waveform generators and analog TV receivers, 450 mA heater, Noval base
  • 6FJ7Compactron Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 900 mA heater
  • 6FM7Compactron Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 1.05 A heater
  • 6FM8 – Dual diode + high-μ triode used as FM demodulator and AF amplifier, 450 mA heater, Noval base
  • 6FN5/EL300 – 17.6 W Power pentode used as CRT horizontal deflection amplifier, Octal base with anode on top cap; 35FN5/PL300 with a 6.3 V/1.65 A heater
  • 6FQ5, 6FQ5A/6GK5 – VHF Semiremote-cutoff triode used as local oscillator in some analog TV turret tuners, 180 mA heater, Miniature 7-pin base
  • 6FQ7 – See 6CG7/6FQ7
  • 6FR7 – Triode + 10-watts power triode used as CRT vertical deflection oscillator+amplifier, 925 mA heater, Neonoval base
  • 6FS5 – See 6FG5
  • 6FV6 – Sharp-cutoff VHF tetrode, 200 mA heater, Miniature 7-pin base
  • 6FV8, 6FV8A – See 6BR8/6FV8
  • 6FW5 – 18 W Beam power tetrode used as CRT horizontal deflection amplifier, 1.2 A heater, 6-pin Octal base
  • 6FW7 – Subminiature, shielded dual medium-μ VHF triode with a base anticipating the Nuvistor, used as oscillator/mixer, 300 mA heater
  • 6FX4 – 1.25 kV, 2×270 mA Full-wave rectifier, 800 mA heater, Miniature 7-pin base
  • 6FX7 – Subminiature, shielded dual medium-μ VHF triode with a base anticipating the Nuvistor, used as cascode amplifier, 300 mA heater
  • 6FY5/EC97 – Frame-grid, high-μ VHF triode, Miniature 7-pin base; 2FY5/XC97 or 4FY5/PC97 with a 6.3 V/200 mA heater
  • 6FY7Compactron Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 1.05 A heater
  • 6GA8/ECC804 – Separate cathodes dual triode, 300 mA heater, Noval base
  • 6GB5/EL500/EL504 – 17 W Beam power pentode used as CRT horizontal deflection amplifier, 1.38 A heater, Magnoval base with anode on top cap
  • 6GC5 – 12 W AF Beam power pentode, 1.2 A heater, Neonoval base
  • 6GC6 – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, 6-pin Octal base with anode on top cap
  • 6GD7 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 380 mA heater, Noval base
  • 6GE5 – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater
  • 6GE8 (7734) – Low-μ triode + sharp-cutoff pentode used as voltage regulator, 900 mA heater, Noval base
  • 6GF5 – 9 W Compactron Beam power pentode used as CRT horizontal deflection amplififer, 1.2 A heater
  • 6GF7, 6GF7A – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 985 mA heater, Novar base
  • 6GH8, 6GH8A – Medium-μ triode + sharp-cutoff pentode used as CRT horizontal deflection oscillator, 450 mA heater, Noval base
  • 6GJ5, 6GJ5A (Evacuation tip at bottom of shorter envelope) – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, Novar base with anode on top cap
  • 6GJ7/ECF801 – VHF Frame-grid triode/pentode oscillator/mixer used in analog TV tuners, 410 mA heater, Noval base
  • 6GJ8 – Triode + pentode used as CRT horizontal deflection oscillator, 600 mA heater, Noval base
  • 6GK5/6FQ5A – See 6FQ5
  • 6GK6 – 13.2 W Beam power pentode used as audio power amplifier or CRT cathode driver, 760 mA heater, Noval base
  • 6GK7 – Dual-control video-IF pentode with a sharp-cutoff control grid and a remote-cutoff suppressor grid for AGC, 300 mA heater, Noval base
  • 6GL7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 1.05 A heater, Octal base
  • 6GM5 – 19 W AF Beam power pentode, 800 mA heater; 7591 or 7868 with a Noval base
  • 6GM6 – Semiremote-cutoff IF pentode, 400 mA heater, Miniature 7-pin base
  • 6GM8/ECC86 – Dual low (6.3-25 V) anode voltage triode, 330 mA heater, Noval base
  • 6GN6 – Remote-cutoff RF/IF pentode, 300 mA heater, Miniature 7-pin base
  • 6GN8 – See 6EB8/6GN8
  • 6GQ7 – Triple diode used as AM/FM demodulator, 450 mA heater, Noval base
  • 6GS7 – VHF Triode/pentode oscillator/mixer, 375 mA heater, Noval base
  • 6GS8 – See 6BU8/6GS8
  • 6GT5, 6GT5A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, Novar base
  • 6GU5 – See 6FG5
  • 6GU7 – Medium-μ dual triode used as CRT vertical/horizontal oscillator or chroma amplifier, 600 mA heater, Noval base
  • 6GV5 – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, anode on top cap
  • 6GV7/ECF805 – VHF Frame-grid triode/remote-cutoff pentode oscillator/mixer used in analog TV tuners, Noval base; 7GV7/PCF805 with a 6.3 V/350 mA heater
  • 6GV8/ECL85 = 6Ф5П6F5P – Triode + 7-watts power pentode used as CRT vertical deflection oscillator+amplifier, 900 mA heater, Noval base
  • 6GW5 – Frame-grid VHF triode, 190 mA heater, Miniature 7-pin base
  • 6GW6 – See 6DQ6B/6GW6
  • 6GW8/ECL86 – AF Triode + 9-watts power pentode used as audio or CRT vertical deflection oscillator+amplifier, 700 mA heater, Noval base
  • 6GX6 – Dual-control, sharp-cutoff pentode used as FM quadrature demodulator, 450 mA heater, Miniature 7-pin base
  • 6GX7 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 400 mA heater, Noval base
  • 6GY5 – 18 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.5 A heater
  • 6GY6 – Dual-control, sharp-cutoff pentode used as gated AGC amplifier/keyer/noise inverter, 450 mA heater, Miniature 7-pin base
  • 6GY8 – Triple high-μ VHF triode used as Autodyne or AFC reactance[68] circuit in FM tuners, 450 mA heater, Noval base, cathode 3, control grid 1 and one side of the heater share pin 4
  • 6GZ5 – 4.8 W AF Power pentode, 380 mA heater, Miniature 7-pin base
  • 6HA5/6HM5/EC900 (6HA5S) – Shielded, frame-grid, vari-μ VHF triode, Miniature 7-pin base; 3HM5/3HA5/LC900, 4HM5/4HA5/PC900 or 2HM5/2HA5/XC900 with a 6.3 V/185 mA heater
  • 6HA6 – 8 W Power pentode used as CRT cathode driver, 710 mA heater, Noval base
  • 6HB5 – 18 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.5 A heater
  • 6HB6 – 10 W Power pentode used as CRT vertical deflection amplifier, 760 mA heater, Noval base
  • 6HB7 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6HC8 – Triode + 11-watts power pentode, 1.2 A heater, Noval base
  • 6HD5 – 24 W Compactron Beam power tetrode used as CRT horizontal deflection amplifier, 2.25 A heater
  • 6HD7 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6HE5/6JB5/6JC5 – 12 W Compactron Beam power tetrode used as CRT vertical deflection amplifier, 800 mA heater
  • 6HE7Compactron High-perveance CRT horizontal deflection output booster/damper/efficiency diode + 10-watts beam power pentode used as CRT horizontal deflection amplifier, 2.7 A heater
  • 6HF5 – 28 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.25 A heater, anode on top cap
  • 6HF8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 750 mA heater, Noval base
  • 6HG5 – See 6AQ5/EL90
  • 6HG8/ECF86 – VHF Frame-grid, medium-μ triode/sharp-cutoff pentode oscillator/mixer, 340 mA heater, Noval base
  • 6HJ5 – 24 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.25 A heater
  • 6HJ8 – High-perveance diode + sharp-cutoff pentode used as audio/video detector or gated AGC amplifier/keyer/noise inverter or DC restorer, and IF or video amplifier, 450 mA heater, Noval base
  • 6HK5 – Frame-grid, vari-μ VHF triode, 190 mA heater, Miniature 7-pin base
  • 6HK8 – Dual VHF triode, 400 mA heater, Noval base
  • 6HL5 – 12 W AF Beam power tetrode, 950 mA heater, Noval base
  • 6HL8 – Medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video or IF amplifier, 600 mA heater, Noval base
  • 6HM5 – See 6HA5/6HM5/EC900
  • 6HM6 – Sharp-cutoff IF pentode, 300 mA heater, Noval base
  • 6HQ5 – Sharp-cutoff VHF triode, 200 mA heater, Miniature 7-pin base
  • 6HQ6 – Semiremote-cutoff IF pentode, 300 mA heater, Miniature 7-pin base
  • 6HR5 – See 6AQ5/EL90
  • 6HR6 – Semiremote-cutoff IF pentode, 450 mA heater, Miniature 7-pin base
  • 6HS5 – 5.5 kV, 30 W, 325 mApeak Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 1.5 A heater
  • 6HS6 – Sharp-cutoff IF pentode, 450 mA heater, Miniature 7-pin base
  • 6HS8 – See 6BU8/6GS8
  • 6HT6 – Semiremote-cutoff IF pentode, 300 mA heater, Noval base
  • 6HU8/ELL80 – 2×6 W Dual AF power pentode, 550 mA heater, Noval base
  • 6HV5A – 5.5 kV, 35 W, 325 mApeak Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 1.8 A heater, anode on top cap
  • 6HW8 – See 6AR8
  • 6HZ5/6JD5/6JH5 – 3.5 kV, 35 W, 300 mApeak Compactron Beam power triode with a 2nd grid ("beam plate") connected to the cathode (technically a tetrode), used as EHV shunt regulator in analog color TV receivers, Uh-c=-200...+450 V, 2.4 A heater
  • 6HZ6 – Dual-control, sharp-cutoff pentode used as FM quadrature demodulator, 450 mA heater, Miniature 7-pin base
  • 6HZ8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 1.125 A heater, Noval base
  • 6JA5Compactron Beam power pentode used as CRT vertical deflection amplifier, 1 A heater
  • 6JA8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or phase inverter/splitter/comparator, and CRT cathode driver, 750 mA heater, Noval base
  • 6JB5 – See 6HE5/6JB5/6JC5
  • 6JB6, 6JB6A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, Novar base with anode on top cap
  • 6JC5 – See 6HE5/6JB5/6JC5
  • 6JC6, 6JC6A – Sharp-cutoff IF pentode, 300 mA heater, Noval base
  • 6JC8 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6JD5 – See 6HZ5/6JD5/6JH5
  • 6JD6 – Sharp-cutoff IF pentode, 300 mA heater, Noval base
  • 6JE6 (24 W), 6JE6A (30 W), 6JE6C/6LQ6/6MJ6 (30 W) – Beam power pentode used as CRT horizontal deflection amplifier, 2.5 A heater, Novar base with anode on top cap
  • 6JE8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 780 mA heater, Noval base
  • 6JF6 – 17 W Beam power pentode used as CRT horizontal deflection amplifier, 1.6 A heater, Novar base with anode on top cap
  • 6JG5 – Sharp-cutoff pentode used as video amplifier, 525 mA heater, Noval base
  • 6JG6, 6JG6A – 17 W Beam power pentode used as CRT horizontal deflection amplifier, 1.6 A heater, Novar base
  • 6JH5 – See 6HZ5/6JD5/6JH5
  • 6JH6 – Semiremote-cutoff IF pentode, 300 mA heater, Miniature 7-pin base
  • 6JH8 – See 6AR8
  • 6JK5 – 5.5 kV, 35 W, 325 mApeak Compactron Beam power triode used as EHV shunt regulator in analog color TV receivers, 1.8 A heater, anode on top cap
  • 6JK6 – Sharp-cutoff IF pentode, 350 mA heater, Miniature 7-pin base
  • 6JK8 – Dual dissimilar triode used as frame-grid, high-μ VHF preamplifier and medium-μ oscillator/mixer in FM tuners, 400 mA heater, Noval base
  • 6JL6 – Semiremote-cutoff IF pentode, 350 mA heater, Miniature 7-pin base
  • 6JL8 – Medium-μ triode + 5-watts power pentode, 750 mA heater, Noval base
  • 6JM6, 6JM6A – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, anode on top cap
  • 6JN6, 6JN6A – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater
  • 6JN8 – Medium-μ triode + sharp-cutoff pentode, 450 mA heater, Noval base
  • 6JQ6 – 10 W Beam power tetrode used as CRT vertical deflection amplifier, integral diode internally connected to the suppressor grid to prevent it from becoming positive, 1.2 A heater, Noval base
  • 6JR6 – 17 W Beam power tetrode used as CRT horizontal deflection amplifier, 1.6 A heater, Novar base
  • 6JS6 (28 W), 6JS6A (28 W), 6JS6C (30 W) – Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.25 A heater
  • 6JT6, 6JT6A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 1.2 A heater, Novar base
  • 6JT8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 725 mA heater, Noval base
  • 6JU8, 6JU8A – 9 mA Quad diode used in FM-stereo demuxers or as color killer phase detector, units 1&2 and 3&4 internally series-connected, 600 mA heater, Noval base
  • 6JV8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 600 mA heater, Noval base
  • 6JW6 – 11.5 W Frame-grid power pentode used as CRT cathode driver, 600 mA heater, Noval base
  • 6JW8/ECF802 – Triode + sharp-cutoff pentode used as CRT horizontal deflection oscillator and reactance tube, 430 mA heater, Noval base
  • 6JZ6 – 18 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.5 A heater
  • 6JZ8Compactron Medium-μ triode + 7-watts beam power pentode used as CRT vertical deflection oscillator+amplifier, 1.2 A heater
  • 6KA8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, 600 mA heater, Noval base
  • 6KD6 – 33 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.85 A heater
  • 6KD8 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 400 mA heater, Noval base
  • 6KE8 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 400 mA heater, Noval base
  • 6KG6, 6KG6A/EL509 – 40 W Beam power pentode used as CRT horizontal deflection amplifier, 2 A heater, Magnoval base
  • 6KM6 – 20 W Beam power pentode used as CRT horizontal deflection amplifier, 1.6 A heater, Novar base with anode on top cap
  • 6KM8 – Diode + triple-anode sharp-cutoff tetrode used in musical instruments, frequency dividers and complex wave generators, 300 mA heater, Noval base
  • 6KN6 – 30 W Compactron Dual beam power pentode with both sections in parallel used as CRT horizontal deflection amplifier, 3 A heater
  • 6KN8 – Dual VHF triode used as cascode amplifier, 400 mA heater, Noval base
  • 6KR8, 6KR8A – Medium-μ triode + sharp-cutoff pentode used as video amplifier, 750 mA heater, Noval base
  • 6KS6 – See 6BN6/6KS6
  • 6KS8 – High-μ triode + semiremote-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector, and video amplifier, 600 mA heater, Noval base
  • 6KT6 – Semiremote-cutoff pentode used as IF amplifier in analog TV receivers, 300 mA heater, Noval base
  • 6KT8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and IF amplifier, 600 mA heater, Noval base
  • 6KU8 – Dual diode + sharp-cutoff pentode used as horizontal phase detector and video amplifier, 725 mA heater, Noval base
  • 6KV6, 6KV6A – 6.5 kV, 20 W, 580 mApeak Beam power pentode used as EHV shunt regulator in analog color TV receivers, 1.6 A heater, Novar base
  • 6KV8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and audio-IF or video amplifier, 775 mA heater, Noval base
  • 6KY6 – 9 W Frame-grid power pentode used as CRT cathode driver, 520 mA heater, Noval base
  • 6KY8, 6KY8A – High-μ triode + 12-watts beam power pentode used as CRT vertical deflection oscillator+amplifier, 1.1 A heater, Novar base
  • 6KZ8 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 450 mA heater, Noval base
  • 6LB6 – 30 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.25 A heater
  • 6LB8 – Medium-μ triode + sharp-cutoff pentode used as DC voltage amplifier and video amplifier, 725 mA heater, Noval base
  • 6LC6 – Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, Octal base with anode on top cap
  • 6LC8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector and gated AGC amplifier/keyer/noise inverter, 600 mA heater, Noval base
  • 6LD6/EL802 – 6 W Power pentode used as CRT cathode driver in analog color TV receivers, 800 mA heater, Noval base
  • 6LE8 – See 6BU8/6GS8
  • 6LF6/6LX6 – 40 W Compactron Beam power tetrode used in CRT horizontal deflection amplifiers, 2 A heater, anode on top cap
  • 6LF8 – High-μ triode + sharp-cutoff pentode used as video amplifier, 600 mA heater, Noval base
  • 6LG6 – 28 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2 A heater
  • 6LH6A/6LJ6A – 27 kV, 40 W, 1.5 mA Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, Octal base with anode on top cap
  • 6LJ8 – Medium-μ triode + sharp-cutoff pentode used as VHF oscillator/mixer, 400 mA heater, Noval base
  • 6LM8, 6LM8A – Medium-μ triode + semiremote-cutoff pentode used as color burst amplifier, 450 mA heater, Noval base
  • 6LQ6 – See 6JE6
  • 6LQ8 – Medium-μ triode + sharp-cutoff pentode used as audio-IF amplifier or combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and CRT cathode drive, 775 mA heater, Noval base
  • 6LR6 – 30 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.5 A heater
  • 6LR8 – High-μ triode + 14-watts beam power pentode used as CRT vertical deflection oscillator+amplifier, 1.5 A heater, Novar base
  • 6LT8 – Dual diode + pentode used as horizontal oscillator and AFC, 600 mA heater, Noval base
  • 6LU6 – Pentode, 400 mA heater, Miniature 7-pin base
  • 6LU8Compactron High-μ triode + 14-watts beam power pentode used as CRT vertical deflection oscillator+amplifier, 1.5 A heater
  • 6LW6 – Beam power pentode used as CRT horizontal deflection amplifier, 2.65 A heater, Octal base with anode on top cap
  • 6LX6 – See 6LF6/6LX6
  • 6LX8/LCF802 – Medium-μ triode + sharp-cutoff pentode used as horizontal oscillator and reactance tube, 450 mA heater, Noval base
  • 6LY8 – High-μ triode + sharp-cutoff pentode used as video amplifier, 750 mA heater, Noval base
  • 6LZ6 – 30 W Beam power pentode used as CRT horizontal deflection amplifier, 2.3 A heater, Novar base with anode on top cap
  • 6MA6 – 30 kV, 40 W, 1.5 mA Beam power triode used as EHV shunt regulator in analog color TV receivers, 200 mA heater, Octal base with anode on top cap
  • 6MB6Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.25 A heater
  • 6MB8 – Medium-μ triode + sharp-cutoff pentode used as burst amplifier and video amplifier, 400 mA heater, Noval base
  • 6MC6 – 33 W Beam power pentode used as CRT horizontal deflection amplifier, 2.85 A heater, Novar base with anode on top cap
  • 6MD8 – Triple medium-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 900 mA heater, Novar base
  • 6ME6 – 30 W Beam power pentode used as CRT horizontal deflection amplifier, 2.3 A heater, Novar base with anode on top cap
  • 6ME8 – See 6AR8
  • 6MF8Compactron High-μ triode + 12-watts beam power pentode used as CRT vertical deflection oscillator+amplifier, 1.4 A heater
  • 6MG8 – Medium-μ triode + sharp-cutoff pentode used as CRT horizontal deflection oscillator, and combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, 450 mA heater, Noval base
  • 6MH6 – 38.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 2.65 A heater
  • 6MJ6 – See 6JE6
  • 6MJ8Compactron Triple medium-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 900 mA heater
  • 6MK8 – See 6BU8/6GS8
  • 6MN8Compactron Triple high-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 900 mA heater
  • 6MQ8 – Medium-μ triode + sharp-cutoff pentode, 535 mA heater, Noval base
  • 6MU8 – Medium-μ triode + semiremote-cutoff pentode used as color burst amplifier, 600 mA heater, Noval base
  • 6MV8 – High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and IF amplifier, 600 mA heater, Noval base
  • 6MY8Compactron Triode + beam power pentode, 1.45 A heater
  • 6SA7, 6SA7-G, 6SA7-GT – First commercially available heptode pentagrid converter with American grid topology, 300 mA heater, Octal base; derived from 6A7 via 6A8, with the control (#3) grid on pin 8 instead of discarded top cap; Miniature 7-pin version: 6BE6/EK90
  • 6SB7Y (Octal Micanol base), 6BA7 (Noval base) – VHF heptode pentagrid converters with American grid topology, 300 mA heater, 1946
  • 6SC7, 6SC7-GT – Common cathode dual high-μ triode, 300 mA heater, Octal base
  • 6SD7-GT – Semiremote-cutoff RF/IF pentode, 300 mA heater, Octal base
  • 6SE7-GT – Sharp-cutoff pentode, 300 mA heater, Octal base
  • 6SF5, 6SF5-GT – High-μ triode, 300 mA heater, Octal base; derived from 6F5, with the grid on pin 3 instead of discarded top cap
  • 6SF7, 6SF7-GT – Diode + remote-cutoff RF/IF pentode, 300 mA heater, Octal base
  • 6SG7, 6SG7-GT – Semiremote-cutoff RF/IF pentode, 300 mA heater, Octal base
  • 6SH7, 6SH7-GT, 6SH7L – Sharp-cutoff RF/IF pentode, 300 mA heater, Octal base
  • 6SJ7, 6SJ7-GT (Bakelite base), 6SJ7Y (Micanol base) – Dual-control, sharp-cutoff RF pentode, 300 mA heater, Octal base, control grid on pin 4; derived from 6J7, with the control grid on pin 4 instead of discarded top cap, and the screen grid on pin 6; similar to types 1603, 77 and U6A-based type 6C6 (control grid on top cap)
  • 6SK7 = 6К36K3, 6SK7-G, 6SK7-GT – Remote-cutoff pentode used in IF amplifiers of North American radios, 300 mA heater, Octal base; derived from 6K7, with the control grid on pin 4 instead of discarded top cap, and the screen grid on pin 6; Miniature 7-pin version: 6BD6
  • 6SL7-G/ECC35, 6SL7-GT – General purpose dual triode, 300 mA heater, Octal base; similar to 6Н9С6N9S; ruggedized version: 6SL7-WGT
  • 6SN7-G/ECC32, 6SN7-GT = Brimar 13D2, 6SN7-GTA, 6SN7-GTB – Dual medium-μ triode used in audio amplifiers, Hammond organs, television, and extensively in World War II radar and in the ENIAC computer, each section is equivalent to a 6J5, 600 mA heater, Octal base; derived from 6N7-G, 6F8-G discarding the control grid top cap; Noval version: 6CG7/6FQ7, later 12AU7; ruggedized versions: 6SN7-WGT, 6SN7-WGTA, 5692, 6042, 6180, CV1986; similar to 6Н8С6N8S, M-OV/GEC B65
  • 6SQ7, 6SQ7-G, 6SQ7-GT/PBC3 – Dual diode + high-μ triode, 300 mA heater, Octal base; derived from 6Q7, with revised pinout, discarding its control grid top cap
  • 6SR7, 6SR7-GT – Dual diode + medium-μ triode, Octal base; derived from 6R7, with revised pinout, discarding its control grid top cap; 12SR7 with a 6.3 V/300 mA heater
  • 6SS7, 6SS7-GT – Remote-cutoff pentode, Octal base, found in some AA6 radios as both the RF amplifier and first IF. This is the only RETMA tube to have a same-letter repetition; derived from 6S7, with the control grid on pin 4 instead of discarded top cap; 6SK7 with a 6.3 V/150 mA heater
  • 6ST7 – Dual diode + high-μ triode, 300 mA heater, Octal base; derived from 6T7, with revised pinout, discarding its control grid top cap
  • 6SU7-GTY – 6SL7-GT with a Micanol base; avionics version: 6SU7-WGT/6188
  • 6SV7 – Diode + sharp-cutoff pentode, 300 mA heater, Octal base
  • 6SZ7 – Dual diode + high-μ triode, 150 mA heater, Octal base
  • 6ZY5-G – 1.25 kV, 2×120 mA Full-wave rectifier, 300 mA heater, 6-pin Octal base

More of these tubes are listed as equivalents under M-P E - 6.3 V heater

LoVTList of American RETMA tubes

7 prefix - Loctal tubes

These tubes all have a Loctal base and a 6.3 V heater, despite the 7-prefix; actual 7-volts series heater tubes are listed below

  • 7A4 = Philco XXL – 6J5 Medium-μ triode, 300 mA heater, with a Loctal base
  • 7A5 – 5.5 W Beam power pentode, 7 V/800 mA (Sylvania) or 6.3 V/750 mA (Tung-Sol) heater; similar to 6U6-GT
  • 7A6 – Dual diode, 150 mA heater; similar to 6H6
  • 7A7, 7A7-LM – 6SK7-GT Remote-cutoff pentode, 300 mA heater, with a Loctal base
  • 7A8 – The only American-made, commercially available octode pentagrid converter used mostly in Philco radios, produced in 1939 by Sylvania; 7B8 with a suppressor grid and a 150 mA heater
  • 7B4 – 6SF5-GT High-μ triode, 300 mA heater, with a Loctal base
  • 7B5, 7B5-LT – 8.5 W AF Power pentode, 400 mA heater; types 41, 6K6-GT with a Loctal base
  • 7B6, 7B6-LM – Dual diode + high-μ triode, 300 mA heater; type 75 with a Loctal base; similar to 6AV6/EBC91, 6SQ7
  • 7B7 – Remote-cutoff pentode, 150 mA heater
  • 7B8, 7B8-LM – Heptode pentagrid converter, 300 mA heater; 6A7, 6A8 with a Loctal base
  • 7C4 – Detector diode, 150 mA heater
  • 7C5, 7C5-LT – 6V6-GT 12 W Beam power pentode, 450 mA heater, with a Loctal base
  • 7C6 – Dual diode + high-μ triode, 150 mA heater
  • 7C7 – Sharp-cutoff pentode, 7 V/160 mA (Sylvania) or 6.3 V/300 mA (Tung-Sol) heater
  • 7D7 – Triode/heptode oscillator/mixer, 7 V/480 mA heater
  • 7E5 – Medium-μ RF triode, 150 mA heater
  • 7E6 – 6SR7 Dual diode + medium-μ triode, 300 mA heater, with a Loctal base; Miniature 7-pin version: 6BF6
  • 7E7 – Dual diode + semiremote-cutoff pentode, 300 mA heater; similar to 6B8-GT
  • 7F7 – 6SL7-GT Dual high-μ triode, 300 mA heater, with a Loctal base
  • 7F8 – 400 MHz Dual medium-μ triode used as amplifier or converter, 300 mA heater; ruggedized version: 7F8-W
  • 7G7 – Dual-control, sharp-cutoff pentode, 450 mA heater
  • 7G8 – Dual sharp-cutoff tetrode, 7 V/320 mA heater
  • 7H7 – Semiremote-cutoff pentode, 300 mA heater
  • 7J7 – Triode/heptode oscillator/mixer, 300 mA heater; similar to 6J8-G
  • 7K7 – Dual diode + high-μ triode, 300 mA heater; similar to 6AT6/EBC90, 6Q7
  • 7L7 – Dual-control, sharp-cutoff pentode, 300 mA heater
  • 7N76SN7-GT Dual medium-μ triode, 600 mA heater, with a Loctal base
  • 7Q7 – Heptode pentagrid converter, 7 V/320 mA heater; similar to 6SA7
  • 7R7 – Dual diode + remote-cutoff pentode, 300 mA heater
  • 7S7 – Triode/heptode oscillator/mixer, 300 mA heater
  • 7T7 – Sharp-cutoff pentode, 300 mA heater
  • 7V7 – Dual-control, sharp-cutoff pentode, 450 mA heater; 7W7 but with the suppressor grid on pin 4, an internal shield on pin 5, and the cathode on pin 7
  • 7W7 – Sharp-cutoff pentode; 7V7 but with the suppressor grid and internal shield on pin 5, and the cathode on pins 4 and 7
    Note: When substituting a 7V7 for a 7W7 or vice-versa, verify connections on socket pins 4 and 7; pin 5 is usually connected to the chassis
  • 7X6 – Dual 700 V, 450 mA rectifier with separate cathodes used as a voltage doubler, 1.2 A heater
  • 7X7 = Philco XXFM – High-μ triode + common-cathode diode + separate-cathode diode used as FM ratio detector and AF amplifier, 300 mA heater
  • 7Y4 – 1.25 kV, 2×210 mA Full-wave rectifier, 500 mA heater
  • 7Z4 – 1.25 kV, 2×300 mA Full-wave rectifier, 450 mA heater
  • 7AB7 – Sharp-cutoff RF pentode, 150 mA heater
  • 7AD7 – 10 W Power pentode used as wideband IF amplifier or as CRT cathode driver, 600 mA heater
  • 7AF7 – Dual medium-μ triode, 300 mA heater
  • 7AG7 – Sharp-cutoff pentode, 150 mA heater
  • 7AH7 – Remote-cutoff pentode, 150 mA heater
  • 7AJ7 – Sharp-cutoff pentode, 300 mA heater
  • 7AK7Dual-control, sharp-cutoff pentode used in computer equipment, 800 mA heater. Perhaps the first tube specifically designed for computer use

LoVTList of American RETMA tubes

12 volt heater tubes

These tubes all have a 12.6 V heater

LoVTList of American RETMA tubes12 volt heater tubes

For fixed/mobile equipment

Many of their heaters are rated 150 mA and so were popular in AA5 radio receivers; others are rated 300, 450 or 600 mA for use also in analog TV receivers

with a straight heater:

  • 12A6, 12A6-GT – 7.5 W Avionics AF Beam power tetrode, 150 mA heater, Octal base[119]: 45 not related to 2A6 nor 6A6
  • 12A7 – 125 VRMS, 30 mA Half-wave rectifier + power pentode used in one-tube portable phonographs and a few two- and three-tube radios, 300 mA heater, U7A base with top cap; pentode section is similar to type 38; forerunner of such types as 32L7-GT, 70L7-GT and 117L7-GT – not related to 2A7 and 6A7 pentagrid
  • 12A8-G, 12A8-GT – Remote-cutoff heptode pentagrid converter with British grid topology and control (#4) grid on top cap, 150 mA heater, Octal base
  • 12B3 – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Noval base with cathode on top cap
  • 12B6-GM – Diode + high-μ triode, 150 mA heater, Octal base with control grid on top cap
  • 12B7 = 14A7 (Commonly branded 14A7/12B7), 12B7-ML – Remote-cutoff pentode, 150 mA heater, Loctal base
  • 12B8-GT – Triode + remote-cutoff pentode, 300 mA heater, Octal base with pentode control grid on top cap
  • 12C5/12CU5 – 6 W AF Beam power pentode, 600 mA heater, Miniature 7-pin base
  • 12C8, 12C8-G, 12C8-GT – Dual diode + semiremote-cutoff pentode, Octal base with control grid on top cap; 6B8 with a 150 mA heater
  • 12D4, 12D4A – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, 6-pin Octal base
  • 12E5-GT – Triode, 150 mA heater, 6-pin Octal base
  • 12F5-GT – High-μ triode, 150 mA heater, 7-pin Octal base with grid on top cap
  • 12F8 – Dual diode + remote-cutoff pentode used as detector and AF amplifier, 150 mA heater, Noval base
  • 12G4 – Medium-μ triode, 150 mA heater; 12J5 with a Miniature 7-pin base
  • 12G11Compactron Dual-control, sharp-cutoff pentode + 6.5-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 600 mA heater
  • 12H6 – Dual diode, 150 mA heater, 7-pin Octal base
  • 12J5, 12J5-GT – Medium-μ triode, 6-pin Octal base; 6J5-GT with a 12.6 V/150 mA heater; avionics version: 12J5-WGT
  • 12J7-GT – Sharp-cutoff pentode, 150 mA heater, 7-pin Octal base with control grid on top cap
  • 12K7-G, 12K7-GT – Remote-cutoff pentode, 150 mA heater, 7-pin Octal base with control grid on top cap
  • 12K8, 12K8-GT – Triode/hexode oscillator/mixer, 150 mA heater, Octal base with hexode control grid #1 on top cap
  • 12L6-GT – 10 W Beam power tetrode, Octal base; 6W6-GT, 25L6-GT or 50L6-GT with a 12.6 V/600 mA heater
  • 12L8-GT – 2×2.5 W Common cathode dual power pentode used as a parallel-connected or push-pull output amplifier, 150 mA heater, Octal base
  • 12Q7-G, 12Q7-GT – Dual diode + high-μ triode, 150 mA heater, 7-pin Octal base with grid on top cap
  • 12R5 – 4.5 W Beam power pentode used as CRT vertical deflection amplifier, 600 mA heater, Miniature 7-pin base
  • 12S7/UAF42 – Diode + remote-cutoff RF/IF/AF pentode, 100 mA heater, Rimlock base
  • 12S8-GT – Triple diode + high-μ triode, 150 mA heater, Octal base with grid on top cap
  • 12T10Compactron Dual-control, sharp-cutoff pentode + 10-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 450 mA heater
  • 12U5-G – Tuning indicator; 6U5-G with a 12.6 V/150 mA heater
  • 12V6-GT – 12 W Beam power pentode used as audio power amplifier or CRT vertical deflection amplifier, 6- or 7-pin Octal base; 5V6 or 6V6 with a 12.6 V/225 mA heater
  • 12W6-GT – 12 W Beam power pentode used as audio power amplifier or CRT vertical deflection amplifier, 600 mA heater, 6- or 7-pin Octal base
  • 12X3 – 7 kV, 10 mA Half-wave rectifier, 650 mA heater, UX4 base
  • 12X4 – 1.25 kV, 2×210 mA Full-wave rectifier, Miniature 7-pin base; 6X4/6BX4/EZ90 with a 12.6 V/300 mA heater
  • 12Y4 – 420 V, 2×8 mA Full-wave rectifier, 150 mA heater, O5A European 5-pin base
  • 12Z3 – Half-wave rectifier, 300 mA heater, UX4 base
  • 12AB5 – 12 W Beam power tetrode, 200 mA heater, Noval base[120]
  • 12AC5/UF41 – Remote-cutoff RF pentode, 100 mA heater, Rimlock base
  • 12AC10Compactron Triple high-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 300 mA heater
  • 12AD5 – Remote-cutoff RF pentode, 100 mA heater, Noval base
  • 12AE6, 12AE6A – Dual diode + medium-μ triode used as detector and AF amplifier, 150 mA heater, Miniature 7-pin base
  • 12AE10Compactron Sharp-cutoff pentode + 6-watts beam power tetrode, 450 mA heater[120]
  • 12AF3 – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Noval base with cathode on top cap
  • 12AF6 – Remote-cutoff RF/IF pentode, 150 mA heater, Miniature 7-pin base
  • 12AF11Compactron High-μ triode + medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and video amplifier, 450 mA heater
  • 12AH7-GT = 12Н11С12N11S – Dual medium-μ triode, 150 mA heater, Octal base
  • 12AJ6 – Dual diode + medium-μ triode, 150 mA heater, Miniature 7-pin base
  • 12AJ7/HCH81 – Triode/remote-cutoff heptode oscillator/mixer, 150 mA heater, Noval base; 19D8/UCH81 with a 12.6 V/150 mA heater
  • 12AL5/HAA91 – Dual diode with separate cathodes, Miniature 7-pin base; 6AL5/EAA91, UAA91 or 3AL5/XAA91 with a 12.6 V/150 mA heater
  • 12AL11Compactron Dual-control, sharp-cutoff pentode + 10-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 450 mA heater
  • 12AQ5 (HL90) – 12 W Beam power pentode used as audio power amplifier or CRT vertical deflection amplifier, 225 mA heater, Miniature 7-pin base
  • 12AS5 – 5.5 W AF Beam power pentode, 400 mA heater, Miniature 7-pin base
  • 12AT6/HBC90 – Dual diode + triode, 150 mA heater, Miniature 7-pin base; superseded by 12AV6/HBC91 in consumer radios
  • 12AU6/HF94, 12AU6A – Sharp-cutoff RF pentode, 150 mA heater, Miniature 7-pin base
  • 12AU8 – Medium-μ triode + sharp-cutoff pentode, 300 mA heater, Noval base
  • 12AV5-GA – 11 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, Octal base
  • 12AV6/HBC91, 12AV6A – Dual diode + high-μ triode, Miniature 7-pin base; 6AV6/EBC91 with a 12.6 V/150 mA heater
  • 12AW6 – Sharp-cutoff pentode, 150 mA heater, Miniature 7-pin base
  • 12AX3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater
  • 12AX4-GT, 12AX4-GTA, 12AX4-GTB – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, 5-pin Octal base
  • 12AY3, 12AY3A – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Novar base
  • 12BA6/HF93, 12BA6A – Remote-cutoff pentode, Miniature 7-pin base; 6BA6/EF93 with a 12.6 V/150 mA heater
  • 12BA7 – VHF heptode pentagrid converter with American grid topology, Noval base; 6BA7 with a 12.6 V/150 mA heater
  • 12BD6 – Remote-cutoff RF/IF pentode, 150 mA heater, Miniature 7-pin base
  • 12BE3, 12BE3ACompactron CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater
  • 12BE6/HK90, 12BE6A – Heptode pentagrid converter with American grid topology, Miniature 7-pin base; 6BE6/EK90 with a 12.6 V/150 mA heater
  • 12BF6 – Dual diode + medium-μ triode, 150 mA heater, Miniature 7-pin base
  • 12BF11Compactron Dual-control, sharp-cutoff pentode + 6.5-watts beam power pentode used as FM quadrature demodulator and AF power amplifier, 600 mA heater
  • 12BK5 – 9 W AF Beam power pentode, 600 mA heater, Noval base
  • 12BK6 – Common cathode dual diode + high-μ AF triode, Miniature 7-pin base; 6BK6 or 26BK6 with a 12.6 V/150 mA heater
  • 12BL6 – Semiremote-cutoff RF/IF pentode, 150 mA heater, Miniature 7-pin base
  • 12BN6, 12BN6AGated-beam discriminator pentode used as FM quadrature demodulator, Miniature 7-pin base; 3BN6, 4BN6, 6BN6 with a 12.6 V/150 mA heater
  • 12BQ6-GT, 12BQ6-GA, 12BQ6-GTB/12CU6 – 11 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, Octal base
  • 12BR3 – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Noval base
  • 12BS3, 12BS3A/12DW4A – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Novar base
  • 12BT3Compactron CRT horizontal deflection output booster/damper/efficiency diode, 450 mA heater
  • 12BT6 – Dual diode + high-μ triode used as detector and AF amplifier, 150 mA heater, Miniature 7-pin base
  • 12BU6 – Dual diode + low-μ triode, 150 mA heater, Miniature 7-pin base
  • 12BV11Compactron Dual sharp-cutoff, dual-control pentode used as color demodulator, 450 mA heater
  • 12BW4 – 1.275 kV, 2×350 mA Full-wave rectifier, 450 mA heater, Noval base
  • 12BX6 – Sharp-cutoff RF/IF/video pentode, Noval base; 3BX6/XF80, 6BX6/EF80 12BX6 or 19BX6/UF80 with a 12.6 V/150 mA heater
  • 12BZ6 – Semiremote-cutoff IF pentode, 150 mA heater, Miniature 7-pin base
  • 12CA5 – 5 W AF Beam power tetrode, 600 mA heater, Miniature 7-pin base
  • 12CK3/12CL3 – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Novar base
  • 12CM6 – 8 W Beam power pentode used as audio power amplifier or CRT vertical deflection amplifier, 225 mA heater, Noval base
  • 12CR5 – 11 W Beam power tetrode used as CRT horizontal deflection amplifier, 600 mA heater, Noval base with anode on top cap
  • 12CR6 – Diode + remote-cutoff pentode, 150 mA heater, Miniature 7-pin base
  • 12CS6 – Sharp-cutoff heptode with American grid topology, used as sync sep/clipper, 150 mA heater, Miniature 7-pin base
  • 12CT3 – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, Noval base
  • 12CT8 – Triode + video pentode, 300 mA heater, Noval base
  • 12CU5 – See 12C5/12CU5
  • 12CU6 – See 12BQ6-GT
  • 12DB5 – 10 W Beam power tetrode, 600 mA heater, Noval base
  • 12DJ8 – Dual VHF triode used as cascode amplifier, 180 mA heater, Noval base
  • 12DK6 – Sharp-cutoff IF pentode, 150 mA heater, Miniature 7-pin base
  • 12DM4, 12DM4A – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, 5-pin Octal base
  • 12DM5 – 5.5 W AF Beam power pentode, 450 mA heater, Miniature 7-pin base
  • 12DQ4 – CRT horizontal deflection output booster/damper/efficiency diode, 600 mA heater, 5-pin Octal base
  • 12DQ6A, 12DQ6B/12GW6 – 18 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, 5, 6, or 7-pin Octal base
  • 12DT5 – 9 W Beam power tetrode, Noval base; 6DT5 or 25DT5 with a 12.6 V/600 mA heater
  • 12DT6 – Dual-control pentode used as FM quadrature demodulator; 3DT6, 4DT6, 6DT6 with a 12.6 V/150 mA heater
  • 12DT8 – High-μ dual triode used as RF amplifier or oscillator/mixer, 150 mA heater, Noval base
  • 12DW4A – See 12BS3A/12DW4A
  • 12DW5 – Beam power pentode used as CRT vertical deflection amplifier, 600 mA heater, Noval base
  • 12DZ8 – High-μ AF triode + 6.5-watts AF power pentode, 12.0 V/450 mA heater, Noval base
  • 12ED5 – 6.25 W AF Beam power pentode, 450 mA heater, Miniature 7-pin base
  • 12EF6 – 10 W Beam power pentode used as CRT vertical deflection amplifier, 450 mA heater, Octal base
  • 12EH5 – 5.5 W AF Beam power pentode, 600 mA heater, Miniature 7-pin base
  • 12EN6 – 7 W Beam power pentode used as CRT vertical deflection amplifier, 600 mA heater, 7-pin Octal base
  • 12EQ7 – Diode + sharp-cutoff pentode used as detector and IF amplifier, 150 mA heater, Noval base
  • 12FB5 – Power pentode used as CRT vertical deflection amplifier, 300 mA heater, Noval base
  • 12FQ7 – Medium-μ dual triode used as CRT horizontal and vertical deflection oscillator, Noval base; 6CG7/6FQ7, 8CG7/8FQ7 with a 12.6 V/300 mA heater
  • 12FQ8 – Common cathode, dual split-anode triode used in musical instruments, frequency dividers and complex wave generators, 150 mA heater, Noval base[121]
  • 12FX5 – 5.5 W AF Beam power pentode, Miniature 7-pin base; 19FX5 or 60FX5 with a 12.6 V/450 mA heater
  • 12GC6 – 17.5 W Beam power tetrode used as CRT horizontal deflection amplifier, 600 mA heater, 6-pin Octal base
  • 12GE5 – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater
  • 12GJ5, 12GJ5A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, Novar base
  • 12GN6 – Remote-cutoff RF/IF pentode, 150 mA heater, Miniature 7-pin base
  • 12GT5, 12GT5A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, Novar base
  • 12GW6 – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, 6-pin Octal base
  • 12HE7Compactron High-perveance CRT horizontal deflection output booster/damper/efficiency diode + 10-watts beam power pentode used as CRT horizontal deflection amplifier, 1.35 A heater
  • 12HL5 – 12 W AF Beam power tetrode, 450 mA heater, Noval base
  • 12HU8/PLL80 – 2×6 W Dual AF power pentode, 300 mA heater, Noval base
  • 12JB6, 12JB6A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, Novar base
  • 12JF5 – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater
  • 12JN6, 12JN6A – 17.5 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater
  • 12JN8 – Medium-μ triode + sharp-cutoff pentode, 225 mA heater, Noval base
  • 12JQ6 – 10 W Beam power tetrode with integral diode used as CRT vertical deflection amplifier, 600 mA heater, Noval base
  • 12JS6 – 28 W Compactron Beam power pentode used as CRT horizontal deflection amplifier, 1.125 A heater
  • 12JT6, 12JT6A – 17.5 W Beam power pentode used as CRT horizontal deflection amplifier, 600 mA heater, Novar base
  • 12KL8 – Diode + sharp-cutoff pentode, 150 mA heater, Noval base
  • 12MD8 – Triple medium-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 450 mA heater, Novar base
  • 12MN8Compactron Triple high-μ triode used as NTSC chroma signal demodulator matrix in analog color TV receivers, 450 mA heater
  • 12SA7, 12SA7-GT – Heptode pentagrid converter with American grid topology, 150 mA heater; 12BE6/HK90 with an Octal base
  • 12SC7 = 12Н10С12N10S – Dual high-μ AF triode used as amplifier or phase inverter, 150 mA heater, Octal base
  • 12SF5, 12SF5-GT – High-μ triode, 150 mA heater, Octal base; derived from 12F5, with the grid on pin 3 instead of discarded top cap
  • 12SF7, 12SF7-GT – Diode + remote-cutoff RF/IF pentode, 150 mA heater, Octal base
  • 12SG7 – Remote-cutoff RF/IF pentode, 150 mA heater, Octal base
  • 12SJ7, 12SJ7-GT – Sharp-cutoff RF/AF pentode, 150 mA heater, Octal base; derived from 12J7, with the control grid on pin 4 instead of discarded top cap, and the screen grid on pin 6
  • 12SK7, 12SK7-GT – Remote-cutoff pentode, 150 mA heater; 12BA6/HF93 with an Octal base; derived from 12K7 with the control grid on pin 4 instead of top cap, and the screen grid on pin 6
  • 12SL7-GT – High-μ dual triode used as AF or DC voltage amplifier, 150 mA heater, Octal base
  • 12SN7-GT, 12SN7-GTA – Medium-μ dual triode used as phase inverter or CRT horizontal or vertical oscillator, 300 mA heater, Octal base; ruggedized version: 12SN7-WGT
  • 12SQ7, 12SQ7-GT – Dual diode + triode, 150 mA heater; 12AV6/HBC91 with an Octal base; derived from 12Q7, with revised pinout, discarding its control grid top cap
  • 12SR7, 12SR7-GT – Dual diode + triode used as detector and AF amplifier, Octal base; 6SR7 with a 12.6 V/150 mA heater

with a center-tapped heater, used in:

  1. Dual-system (6-volts and 12-volts) car radios,
  2. Parallel heater circuits - the same tube may be wired for 6.3 or 12.6V,
  3. Series heater strings - the same tube may be wired for e.g. 150 or 300mA
  • 12A4 – High-perveance triode used as CRT vertical deflection amplifier, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base
  • 12A5 – 8.25 W Power pentode mostly used in pre-war car radios, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, U7A base
  • 12B4A – 5.5 W Power triode, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base[120]
  • 12H4 – Triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Miniature 7-pin base
  • 12Z5 = 6Z5 – Full-wave rectifier used as renewal type for Majestic receivers, U6A base, marketed as "6Z5/12Z5"; similar to types 6Z4/84 and 6X5, but with a center-tapped 12.6 V/400 mA resp. 6.3 V/800 mA heater
  • 12AD7 – Dual high-μ, low-microphonics triode, center-tapped 12.6 V/225 mA resp. 6.3 V/450 mA heater, Noval base
  • 12AH8 – Triode/heptode oscillator/mixer, center-tapped 12.6 V/150mA resp. 6.3 V/300 mA heater, Noval base
  • 12AT7/ECC81 = M-OV/GEC B309 (12AT7-WA, 6060, 6201, M8162) – Dual high-μ triode used as amplifier/mixer in VHF tuners, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater[120]
  • 12AU7/ECC82 = M-OV/GEC B329 (12AU7-WA, 6067, 6189, M8136) – Dual medium-μ AF triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater.[120] Two 6C4/EC90s in one envelope;[122] however, it is only specified as an audio frequency tube
  • 12AV7 (5965) – Dual medium-μ VHF triode used as amplifier or mixer, center-tapped 12.6 V/225 mA resp. 6.3 V/450 mA heater[123]
  • 12AX7/ECC83 = M-OV/GEC B339 (12AX7S, 12AX7-WA, 6057, 6681, M8137) – Dual high-μ AF triode used in high-gain audio amplifiers, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater; very similar to triode section of 6AV6/EBC91;[120] similar to 6Н2П6N2P
  • 12AY7 – Dual low-noise, medium-μ triode used as preamplifier, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater[120]
  • 12AZ7, 12AZ7A – Dual medium-μ triode used as AF amplifier or combined oscillator/mixer, center-tapped 12.6 V/225 mA resp. 6.3 V/450 mA heater, Noval base[124][120]
  • 12BH7, 12BH7A – 2×3.5 W Dual medium-μ power triode, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater[125][120]
  • 12BR7, 12BR7A – Dual diode + triode, center-tapped 12.6 V/225 mA resp. 6.3 V/450 mA heater; 9BR7 with a different heater – not related to 6BR7 pentode
  • 12BV7, 12BY7/EL180, 12DQ7 – Power pentodes used as CRT cathode driver, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base[126]
  • 12BZ7 – Dual high-μ triode used as combined sync sep/clipper/amplifier/phase detector, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base
  • 12DF5 – Dual 1.275 kV, 350 mA rectifier with separate cathodes used as a voltage doubler, center-tapped 12.6 V/450 mA resp. 6.3 V/900 mA heater, Noval base
  • 12DF7 – Dual triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base; low-microphonics variant of 12AX7/ECC83
  • 12DM7 – Dual high-μ triode, low hum, center-tapped 12.6 V/130 mA resp. 6.3 V/260 mA heater, Noval base
  • 12DQ7 – See 12BV7
  • 12DT7 – Dual high-μ AF triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • 12DW7/ECC832 (7247) – Dual dissimilar AF triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base; one half 12AU7/ECC82-type triode, other half 12AX7/ECC83-type triode
  • 12GN7/12HG7 – Sharp-cutoff pentode used as video amplifier, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base
  • 12HL7 – Sharp-cutoff pentode used as video amplifier, center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater, Noval base

LoVTList of American RETMA tubes12 volt heater tubes

For mobile equipment

  • 12J8 – Dual diode + low (12.6-30 V) anode voltage power tetrode, 325 mA heater, Noval base
  • 12K5 – Low (12.6-30 V) anode voltage power tetrode with a space charge grid, 400 mA heater, Miniature 7-pin base
  • 12U7 – Dual low (12.6-30 V) anode voltage, medium-μ triode, center-tapped 12.6 V/150 mA resp. 6.3 V/300 mA heater, Noval base
  • 12AC6 – Low (12.6-30 V) anode voltage remote-cutoff pentode, 150 mA heater, Miniature 7-pin base
  • 12AD6 – Low (10.0-15.9 V) anode voltage sharp-cutoff heptode pentagrid converter with American grid topology, 150 mA heater, Miniature 7-pin base
  • 12AE7 – Dual dissimilar (medium-μ + low-μ), low (12.6-16 V) anode voltage AF triode for use in semi-transistorized car radios, 450 mA heater, Noval base
  • 12AG6 – Low (12.6-16 V) anode voltage heptode pentagrid converter with American grid topology, 150 mA heater, Miniature 7-pin base
  • 12AL8 – Low (12.6-30 V) anode voltage medium-μ triode + power tetrode with a space charge grid, 550 mA heater, Noval base
  • 12CN5 – Low (12.6-16 V) anode voltage sharp-cutoff IF pentode, 450 mA heater, Miniature 7-pin base
  • 12CX6 – Low (12.6-33 V) anode voltage sharp-cutoff pentode, 150 mA heater, Miniature 7-pin base
  • 12CY6 – Low (12.6-16 V) anode voltage sharp-cutoff RF pentode, 200 mA heater, Miniature 7-pin base
  • 12DE8 – Diode + low (12.6-30 V) anode voltage, remote-cutoff pentode, 200 mA heater, Noval base
  • 12DK5 – Low (12.6-16 V) anode voltage sharp-cutoff RF/IF pentode, 300 mA heater, Noval base
  • 12DK7 – Dual diode + low (12.6-30 V) anode voltage power tetrode, 500 mA heater, Noval base
  • 12DL8 – Dual diode + low (12.6-30 V) anode voltage power tetrode with a space charge grid, 550 mA heater, Noval base
  • 12DS7, 12DS7A – Dual diode + low (12.6-16 V) anode voltage power tetrode, 400 mA heater, Noval base
  • 12DU7 – Dual diode + low (12.6-16 V) anode voltage power tetrode, 250 mA heater, Noval base
  • 12DV7 – Dual diode + low (12.6-16 V) anode voltage triode, 150 mA heater, Noval base
  • 12DV8 – Dual diode + low (12.6-16 V) anode voltage power tetrode with a space charge grid, 375 mA heater, Noval base
  • 12DW8 – Diode + dual dissimilar (medium-μ + low-μ), low (12.6-16 V) anode voltage AF triode for use in semi-transistorized car radios, 450 mA heater, Noval base
  • 12DY8 – Low (12.6-16 V) anode voltage medium-μ triode + remote-cutoff pentode, 350 mA heater, Noval base
  • 12DZ6 – Low (12.6-16 V) anode voltage RF pentode, 190 mA heater, Miniature 7-pin base
  • 12EA6 – Low (12.6-16 V) anode voltage IF pentode, 175 mA heater, Miniature 7-pin base
  • 12EC8 – Low (12.6-16 V) anode voltage medium-μ triode + semiremote-cutoff pentode, 225 mA heater, Noval base
  • 12EG6 – Low (12.6-30 V) anode voltage heptode pentagrid converter with American grid topology, both control grids #1 and #3 are sharp-cutoff, 150 mA heater, Miniature 7-pin base
  • 12EK6 – Low (12.6-16 V) anode voltage sharp-cutoff RF/IF pentode, 200 mA heater, Miniature 7-pin base
  • 12EL6 – Dual diode + low (12.6-30 V) anode voltage, high-μ triode, 150 mA heater, Miniature 7-pin base
  • 12EM6 – Diode + low (12.6-30 V) anode voltage power tetrode, 500 mA heater, Noval base
  • 12EZ6 – Low (12.6-30 V) anode voltage sharp-cutoff RF/IF pentode, 175 mA heater, Miniature 7-pin base
  • 12FA6 – Low (12.6-30 V) anode voltage heptode pentagrid converter with American grid topology, 150 mA heater, Miniature 7-pin base; car radio variant of 12BE6/HK90
  • 12FK6 – Low (12.6-16 V) anode voltage dual diode + low-μ triode used as detector, AVC rectifier and AF amplifier, 150 mA heater, Miniature 7-pin base
  • 12FM6 – Dual diode + low (12.6-30 V) anode voltage, medium-μ triode, 150 mA heater, Miniature 7-pin base
  • 12FR8 – Diode + low (12.6-16 V) anode voltage triode + pentode used as IF/AF amplifier and detector, 320 mA heater, Noval base
  • 12FT6 – Dual diode + low (12.6-30 V) anode voltage triode used as detector and AF Amplifier, 150 mA heater, Miniature 7-pin base
  • 12FX8, 12FX8A – Low (12.6-16 V) anode voltage triode/heptode oscillator/mixer, 270 mA heater, Noval base
  • 12GA6 – Low (12.6-16 V) anode voltage heptode pentagrid converter with American grid topology, 150 mA heater, Miniature 7-pin base; similar to 12FA6, but with lower conversion transconductance
  • 12SW7 – Dual diode + low (26.5-250 V) anode voltage triode, 150 mA heater, Octal base
  • 12SX7-GT – Dual low (26.5-300 V) anode voltage triode, 300 mA heater, Octal base
  • 12SY7, 12SY7-GT – Low (26.5-300 V) anode voltage pentagrid converter, 150 mA heater, Octal base

LoVTList of American RETMA tubes

14 prefix - Loctal tubes

These tubes have 12.6 V heaters despite the 14-prefix, intended to indicate a Loctal base. Most draw 150 mA for use in AA5 radio receivers; actual 14-volts series heater tubes are listed below

  • 14A4 – 7A4 Medium-μ triode with a 12.6 V/150 mA heater; 12J5 with a Loctal base
  • 14A5 – 7.5 W Beam power pentode, 150 mA heater
  • 14A7 = 12B7 (Commonly branded 14A7/12B7) – 7A7 Remote-cutoff pentode with a 12.6 V/150 mA heater; 12SK7-GT with a Loctal base
  • 14B6 – 7B6 Dual diode + high-μ triode with a 12.6 V/150 mA heater; similar to 12AV6/HBC91, 12SQ7
  • 14B8 – 7B8 Heptode pentagrid converter with a 12.6 V/150 mA heater; 12A8 with a Loctal base
  • 14C5 – 7C5 Beam power pentode with a 12.6 V/225 mA heater; 12V6-GT with a Loctal base
  • 14C7 – 7C7 Sharp-cutoff pentode with a 12.6 V/150 mA heater
  • 14E6 – 7E6 Dual diode + medium-μ triode with a 12.6 V/150 mA heater; 12SR7 with a Loctal base
  • 14E7 – 7E7 Dual diode + semiremote-cutoff pentode with a 12.6 V/150 mA heater; similar to 12C8
  • 14F7 – 7F7 Dual high-μ triode with a 12.6 V/150 mA heater; 12SL7-GT with a Loctal base
  • 14F8 – 7F8 Medium-μ VHF triode with a 12.6 V/150 mA heater, used as amplifier or converter
  • 14H7 – 7H7 Semiremote-cutoff pentode with a 12.6 V/160 mA heater
  • 14J7 – 7J7 Triode/heptode oscillator/mixer with a 12.6 V/150 mA heater
  • 14N7 – 7N7 Dual medium-μ triode with a 12.6 V/300 mA heater; 12SN7-GT with a Loctal base
  • 14Q7 – 7Q7 Heptode pentagrid converter with a 12.6 V/150 mA heater; similar to 12SA7
  • 14R7 – 7R7 Dual diode + remote-cutoff pentode with a 12.6 V/150 mA heater
  • 14S7 – 7S7 Triode/heptode oscillator/mixer with a 12.6 V/150 mA heater
  • 14W7 – 7W7 Sharp-cutoff pentode with a 14 V/240 mA heater
  • 14X7 – 7X7/XXFM Dual diode + high-μ triode on separate cathodes with a 14 V/160 mA heater, used as FM ratio detector and AF amplifier
  • 14Y4 – 7Y4 1.25 kV, 2×210 mA Full-wave rectifier with a 14 V/320 mA heater
  • 14AF7 = Philco XXD – 7AF7 Dual medium-μ triode with a 12.6 V/150 mA heater

LoVTList of American RETMA tubes

25 volt series heater tubes

For AA5 radio receivers with 150 mA series heater strings

  • 25B8-G, 25B8-GT – Triode + pentode, Octal base
  • 25F5 – 50C5 Beam power pentode with half the heater power, allowing for push-pull output amplifiers with the heater spec of a single 50C5

For AA5 radio receivers with 300 mA series heater strings

  • 25A6, 25A6-G – AF Power pentode; type 43 with an Octal base
  • 25B5 (U6A base), 25N6-G (Octal base) – Triple-Twin AF signal + 4-watts zero bias power triode, internally connected as a cathode follower like today's Darlington transistors; 6B5 resp. 6N6-G with a 25 volt heater
  • 25B6-G (5824) – AF Power pentode, Octal base
  • 25C5 – 50C5 Beam power pentode with a 25 volt heater
  • 25L6 – 12L6 or 50L6 Beam power pentode with a 25 volt heater
    Besides AA5, also popular for high-speed gating, or as a relay or keypunch solenoid driver, in early computers such as the UNIVAC I, where the heater ran off the equipment's 24-volts supply bus. As the 25L6-GT developed cathode interface/poisoning after prolonged periods in cut-off, the EIA-type 6046 was derived from it, which didn't suffer from this problem
  • 25Z4, 25Z4-GT – 125 Vrms, 125 mA Half-wave rectifier, Octal base
  • 25Z5 (U6A base), 25Z6 (Octal base) – Dual 700 V, 450 mA rectifier with separate cathodes used as a voltage doubler

LoVTList of American RETMA tubes

35 volt series heater tubes

For AA5 radio receivers with 150 mA series heater strings

  • 35A5 – 35L6-GT Beam power tetrode with a Loctal base
  • 35B5 – AF Beam power tetrode, Miniature 7-pin base
  • 35C5 – 35B5 with a revised pinout to address concerns that high peak voltage between 4 (heater) and 5 (anode) would promote socket breakdown[127]
  • 35L6-GT – Lower-powered 50L6-GT beam power pentode
  • 35W4 – Half-wave rectifier with a heater tap for a pilot lamp, Miniature 7-pin base
  • 35Y4 – 35Z5-GT Half-wave rectifier with a Loctal base
  • 35Z3 – 35Z4-GT Half-wave rectifier with a Loctal base
  • 35Z4-GT, 35Z5-GT (with a heater tap for a pilot lamp) – Half-wave rectifier, Octal base
  • 35DZ8, 35HB8 – High-μ AF triode + AF power pentode, Noval base
  • 35GL6 – AF Beam power tetrode with a heater tap for a pilot lamp, Miniature 7-pin base

LoVTList of American RETMA tubes

50 volt series heater tubes

For AA5 radio receivers with 150 mA series heater strings

  • 50A5 – 50L6 Beam power tetrode with a Loctal base
  • 50B5 – Higher-powered 35B5 beam power tetrode
  • 50C5 – 50B5 with a revised pinout to address concerns that high peak voltage between 4 (heater) and 5 (anode) would promote socket breakdown[127]
  • 50L6 – 12L6 or 25L6 Beam power tetrode with a 50 volt heater
  • 50X6 (Loctal base), 50Y7-GT (Octal base, heater tap for a pilot lamp) – Dual rectifier with separate cathodes used as a voltage doubler
  • 50DC4 – Higher-powered 35W4 half-wave rectifier
  • 50EH5 – AF Beam power tetrode, some radios that use this tube do not have an audio amplifier section; similar to 50C5 but with higher gain
  • 50HK6 – AF Power pentode with a heater tap for a pilot lamp

LoVTList of American RETMA tubes

117 volt heater tubes

These tubes operate with their heaters connected directly to the 117 volt (now 120 volt) electrical mains of North America. They are indirectly heated and were used in one-tube phonographs and Three-way portable (AC or DC mains, or batteries) radio receivers

LoVTList of American RETMA tubes117 volt heater tubes

Rectifier + beam power tetrodes

  • 117L7-GT = 117M7-GT – 350 V, 75 mA Half-wave rectifier + 6 W AF beam power tetrode, 90 mA heater, Octal base
  • 117N7-GT – 350 V, 75 mA Half-wave rectifier + 5.5 W AF beam power tetrode, 90 mA heater, Octal base
  • 117P7-GT – 330 V, 450 mA Half-wave rectifier + 6 W AF beam power tetrode, 90 mA heater, Octal base

LoVTList of American RETMA tubes117 volt heater tubes

Rectifiers

  • 117Z3 (Miniature 7-pin base), 117Z4-GT (Octal base) – 330 V, 540 mA Half-wave rectifier, 40 mA heater
  • 117Z6-GT – Dual, separate cathodes 700 V, 60 mA rectifier used as a voltage doubler, 75 mA heater, Octal base; some versions have a heater center-tap on pin 1 for 150 mA/58.5 V operation

LoVTList of American RETMA tubes

100 mA series heater tubes

Used in "Power-Saver" radio receivers with series heater strings, also for 220-240V mains

  • 14G6/UBC81 – Dual diode + triode, 14 V heater, Noval base
  • 14K7/UCH42 – Triode/remote-cutoff hexode oscillator/mixer, 14 V heater, Rimlock base
  • 14L7/UBC41 – Shielded dual diode + AF triode, 14 V heater, Rimlock base
  • 14Y7 – Triode/hexode oscillator/mixer, 14 V heater, Noval base - not a Loctal rectifier
  • 18FW6, 18FW6A – Semiremote-cutoff RF/IF pentode, 18 V heater, Miniature 7-pin base
  • 18FX6, 18FX6A – 6BE6/EK90 or 12BE6/HK90 Pentagrid with an 18 V heater
  • 18FY6, 18FY6A – 6AV6/EBC91 or 12AV6/HBC91 Dual diode + triode with an 18 V heater
  • 18GD6, 18GD6A – Sharp-cutoff RF/IF pentode, 18 V heater, Miniature 7-pin base
  • 18GE6 – Dual diode + triode, 18 V heater, Miniature 7-pin base
  • 20EQ7 – 6EQ7 or 12EQ7 Diode + sharp-cutoff pentode with a 20 V heater
  • 20EZ7 – Dual high-μ AF triode, center-tapped 20 V/100 mA resp. 10 V/200 mA heater, Noval base; similar to 407A
  • 32ET5, 32ET5A – Beam power tetrode, 32 V heater, Miniature 7-pin base
  • 34GD5, 34GD5A – 35C5 or 50C5 Beam power tetrode with a 34 V heater
  • 36AM3 – 35W4 Half-wave rectifier with a 36 V heater
  • 40FR5 – AF Power pentode, 40 V heater, Miniature 7-pin base
  • 50BM8/UCL826BM8/ECL82, 11BM8/LCL82, 16A8/PCL82 or 8B8/XCL82 AF Triode + AF power pentode with a 50 V heater
  • 50FA5, 50FK5 – AF Power pentode, 50 V heater, Miniature 7-pin base
  • 60FX5 – 12FX5 or 19FX5 AF Power pentode with a 60 V heater
  • 60HL5 – 6HL5 or 12HL5 Beam power tetrode with a 60 V heater

More of these tubes are listed as equivalents under M-P U - 100 mA heater

LoVTList of American RETMA tubes

150 mA series heater tubes

Used in AA5 radios, and semi-transistorized analog TV receivers with series heater strings

  • 14GT8/7724, 14JG8 – Dual diode + high-μ triode used as FM demodulator and AF amplifier in fixed, series-heated, or mobile, parallel-heated equipment, 14 V heater, Noval base
  • 17EW8/HCC85 – 6AQ8/ECC85, 9AQ8/PCC85 or UCC85 Dual triode with a 17.5 V heater
  • 19HV8 – AF triode + IF pentode, 18.9 V heater, Noval base
  • 19T86T8 Triple diode + triode with an 18.9 V heater; HABC80 with a shorter glass envelope
  • 40B2 – 20 to 60 V Barretter, Octal base, to stabilize against mains voltage fluctuations
  • 50JY6 – Horizontal deflection beam power pentode, 50 V heater, Octal base
  • 56R9Compactron AF triode + beam power pentode, separate heaters for triode (14 V) and pentode (42 V) for flexibility with the series string order
  • 60E3 – Half-wave rectifier, 60 V heater, Miniature 7-pin base
  • 70A7-GT (With heater tap for a pilot lamp), 70L7-GT – Half-wave rectifier + beam power pentode, 70 V heater, Octal base

More of these tubes are listed as equivalents under M-P H - 150 mA heater

LoVTList of American RETMA tubes

300 mA series heater tubes

Most are series heater versions of respective 6-prefix tubes; used in analog TV receivers with series heater strings

  • 4HK5 – 2HK5, 3HK5 or 6HK5 VHF triode with a 4.0 V heater
  • 6AU712AU7/ECC82 Dual AF triode with a center-tapped 300 mA/6.3 V resp. 600 mA/3.15 V heater, Noval base
  • 6AX712AX7/ECC83 Dual AF triode with a center-tapped 300 mA/6.3 V resp. 600 mA/3.15 V heater
  • 6CN7 – 8CN7 Dual common cathode diode + high-μ triode used as reactance tube or combined sync sep/clipper/amplifier/phase detector, center-tapped 300 mA/6.3 V resp. 600 mA/3.15 V heater, Noval base
  • 7AN7/PCC84 – 6CW7/ECC84 Dual VHF triode with a 7.2 V heater – not related to 6AN7/ECH80 triode/hexode
  • 7AU7/XCC82 – 6AU7 Dual triode with a center-tapped 300 mA/7.0 V resp. 600 mA/3.5 V heater
  • 7DJ8 – 6DJ8 Dual VHF triode with a 7 V heater
  • 7FC7/PCC89 – 6FC7/ECC89 Dual VHF triode with a 7.2 V heater
  • 7GS7 – 6GS7 Triode + pentode with a 7.6 V heater
  • 7GV7/PCF805 – 6GV7/ECF805 Triode + pentode with a 7.4 V heater
  • 7HG8/PCF86 – 4HG8/XCF86, 5HG8/LCF86, 6HG8/ECF86 or 8HG8 VHF Triode/pentode oscillator/mixer with a 7.2 V heater
  • 9AK8/PABC806AK8/EABC80 Triple diode + triode with a 9.5 V heater
  • 16Y9 – Pentode + power pentode used as audio-IF amplifier or combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and CRT cathode driver, Decal base; 17Y9/PFL200 with a 16.5 V heater
  • 18A5 – Beam power pentode used as CRT horizontal deflection amplifier, 18.5 V heater, Octal base
  • 42A1 (141 Ω), 49A1 (162 Ω), 55A1 (183 Ω), 80A1 (266 Ω), 86A1 (287 Ω), 92A1 (308 Ω) – Straight ballast resistors used in areas with a stable power grid, Octal base
  • 42A2, 49A2, 55A2, 80A2, 86A2, 92A2 – Straight ballast resistors with tap for 2 pilot lamps
  • 42B2, 49B2, 55B2, 80B2, 86B2, 92B2 – Straight ballast resistors with tap for 1 pilot lamp
  • 50A2 (with tap for 2 pilot lamps), 50B2 (with tap for 1 pilot lamp) – 50 V Barretter, UX4 base, to stabilize against mains voltage fluctuations
  • 58HE7 – 6HE7, 12HE7 or 38HE7 Compactron Booster/damper/efficiency diode + beam power pentode with a 58 V heater

More of these tubes are listed as equivalents under M-P P - 300 mA heater

LoVTList of American RETMA tubes

450 mA series heater tubes

Most are series heater versions of respective 6-prefix tubes; used in analog TV receivers with series heater strings

  • 2CW4 – 6CW4 Nuvistor with a 2.1 V heater
  • 2EN5 – Common cathode dual diode used as a phase comparator, 2.1 V heater, Miniature 7-pin base
  • 4BN6 – 3BN6, 6BN6/6KS6, 12BN6 Gated-beam discriminator with a 4.2 V heater
  • 4CB6 – 6CB6 Pentode with a 4.2 V heater
  • 4DT6 – 3DT6, 6DT6, 12DT6 Pentode with a 4.2 V heater
  • 5HC7 – 4HC7 Compactron Dual dissimilar triode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, 5.6 V heater
  • 6LN8/LCF80 – 6BL8/ECF80, 9A8/PCF80 or 4BL8/XCF80 Triode + pentode with a 6.0 V controlled warm-up heater
  • 7KY6 – 6KY6 Pentode with a 7.3 V heater[128]
  • 7KZ6 – Power pentode used as CRT cathode driver, 7.3 V heater, Noval base
  • 8AC10 – 6AC10, 12AC10A Triple triode with an 8.4 V heater
  • 8B10 – 6B10 Dual diode + dual triode with an 8.5 V heater
  • 8CG7/8FQ76CG7/6FQ7, 12FQ7 Dual triode with an 8.4 V heater
  • 8CN7 – 6CN7 Dual common cathode diode + triode used as reactance tube or combined sync sep/clipper/amplifier/phase detector, center-tapped 225 mA/8.4 V resp. 450 mA/4.2 V heater
  • 9AU7 – 7AU7/XCC82 Dual triode with a center-tapped 225 mA/9.4 V resp. 450 mA/4.7 V heater
  • 10JA8/10LZ8 – 6JA8 High-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase inverter, and CRT cathode driver, 10.5 V heater, Noval base
  • 10JY8 – Medium-μ triode + sharp-cutoff pentode used as combined sync sep/clipper/amplifier/phase inverter, and CRT cathode driver, 10.5 V heater, Noval base
  • 11DS5 – 50B5 or 35B5 Beam power tetrode with an 11.2 V heater
  • 13J10/13Z106J10/6Z10, 10Z10 Pentode + power pentode with a 13.2 V heater
  • 14BL11Compactron Medium-μ triode + high-μ triode + sharp-cutoff video pentode, 14.2 V heater
  • 14BR11Compactron Medium-μ triode + high-μ triode + frame-grid, sharp-cutoff video pentode, 14.2 V heater
  • 17D46DA4/6DM4 Booster/damper/efficiency diode with a 16.8 V heater
  • 17LD8 – Medium-μ triode + power pentode used as CRT vertical deflection oscillator+amplifier, 16.8 V heater, Neonoval base
  • 33GY7Compactron Booster/damper/efficiency diode + beam power pentode, 33.6 V heater
  • 38HE7, 38HK7 – 6HE7, 12HE7, 53HK7 or 58HE7 Compactron Booster/damper/efficiency diode + beam power pentode with a 37.8 V heater
  • 42KN6 – 6KN6 Beam power pentode with a 42 V heater

More of these tubes are listed as equivalents under M-P L - 450 mA heater

LoVTList of American RETMA tubes

600 mA series heater tubes

Most are series heater versions of respective 6-prefix tubes; used in analog color TV receivers with series heater strings

  • 1DY4 – 6DY4 UHF frame-grid triode with a 1.6 V heater
  • 2AF46AF4/EC94 UHF Triode with a 2.35 V heater
  • 2BN4 – 6BN4 VHF triode with a 2.3 V heater
  • 2CY5 – 6CY5 VHF tetrode with a 2.4 V heater
  • 2EA5 – 3EA5 or 6EA5 VHF tetrode with a 2.4 V heater
  • 2EG4Nuvistor High-μ VHF triode, 1.7 volt heater
  • 2ER5/XC95 – 3ER5, 4ER5/PC95 or 6ER5/EC95 VHF Triode with a 2.3 V heater
  • 2ES5 – 6ES5 VHF triode with a 2.35 V heater
  • 2EV5 – 3EV5 (6EV5) VHF tetrode with a 2.4 V heater
  • 2FH5 – 3FH5 or 6FH5 VHF triode with a 2.35 V heater
  • 2FQ5 – 3FQ5, 6FQ5 VHF Triode with a 2.3 V heater
  • 2FV6 – 6FV6 VHF Tetrode with a 2.4 V heater
  • 2FY5/XC97 – 4FY5/PC97 or 6FY5/EC97 VHF Triode with a 2.4 V heater
  • 5AV8 – Medium-μ triode + sharp-cutoff pentode used as CRT vertical deflection oscillator+amplifier, Noval base; 6AN8 with a 4.7 V heater
  • 5DH8 – High-μ triode + sharp-cutoff pentode, 5.2 V heater, Noval base
  • 5J6 – 6J6/ECC91 Dual VHF triode with a 4.7 V/600 mA controlled warm-up heater[129]
  • 5T86T8 Triple diode + high-μ triode with a 4.7 V heater
  • 7EY6 – 6EY6 Beam power pentode with a 7.2 V heater
  • 10DE7 – 6DE7 or 13DE7 Dual dissimilar triode with a 9.7 V heater
  • 10EG7 – Dual dissimilar triode used as CRT vertical deflection oscillator+amplifier, 9.7 V heater, Octal base
  • 16AQ3/XY88 – EY88/6AL3, LY88/20AQ3 or PY88/30AE3 CRT horizontal deflection output booster/damper/efficiency diode with a 16 V heater
  • 25CD6-GA, 25CD6-GB, 25EC6 (110° deflection) – 6CD6 Beam power pentode used as CRT horizontal deflection amplifier, 25 V heater, Octal base
  • 30KD6 – 6KD6 or 36KD6/40KD6 Beam power pentode with a 30 V heater

More of these tubes are listed as equivalents under M-P X - 600 mA heater

LoVTList of American RETMA tubes

12-cell lead-acid battery heater tubes

Used in 24-volts vehicle equipment

  • 26A6 – Remote-cutoff RF pentode, 26.5 V/70 mA heater, Miniature 7-pin base
  • 26A7-GT – 2×2 W Dual low (26.5-50 V) anode voltage AF beam power pentode used as a push–pull audio amplifier, designed for both anode and 26.5 V/600 mA heater to run directly off the standard avionics 28-volts DC bus, Octal base; cf. 13П1С, Shuguang 13P1P
  • 26BK6, 26C6 – Common cathode dual diode + high-μ AF triode, Miniature 7-pin base; 6BK6 or 12BK6 with a 26.5 V/70 mA heater
  • 26D6 – Heptode pentagrid converter with American grid topology, Miniature 7-pin base; 6BE6/EK90 with a 26.5 V/70 mA heater and reduced-specs minimum anode voltage 26.5 V
  • 26E6-G = 26E6-WG – 12.5 W Avionics AF beam power pentode, 26.5 V/300 mA heater, Octal base
  • 26Z5-W – Avionics dual 1.375 kV, 300 mA rectifier with separate cathodes used as a voltage doubler, 26.5 V/200 mA heater, Noval base
  • 28D7-W – 2×3 W Dual low (28-100 V) anode voltage AF beam power pentode used as a push–pull audio amplifier, or as switching element of a self-excited push–pull DC/DC converter to provide up to 725 mW of anode high voltage supply for conventional tubes, both anode and 28 V/400 mA heater run off the avionics 28-volts DC bus, shock resistant up to 350 g, Loctal base

LoVTList of American RETMA tubes

Other tubes

315 mA series heater tubes

  • 16BQ11Compactron Remote-cutoff pentode + sharp-cutoff IF pentode, 16 V heater
  • 16BX11Compactron Medium-μ triode + high-μ triode + sharp-cutoff video pentode, 16 V heater
  • 18AJ10Compactron Dual-control pentode + AF power pentode, 18 V heater
  • 24BF11Compactron Dual-control, sharp-cutoff pentode + beam power pentode, 24.2 V heater
  • 24JZ8Compactron Medium-μ triode + beam power tetrode used as CRT horizontal deflection amplifier, 24.2 V heater
  • 31AL10Compactron High-μ triode + medium-μ triode + beam power tetrode used as combined sync sep/clipper/amplifier/phase detector or gated AGC amplifier/keyer/noise inverter, and CRT vertical deflection oscillator+amplifier, 31.5 V heater
  • 32HQ7Compactron High-perveance CRT horizontal deflection output booster/damper/efficiency diode + beam power pentode, 32.6 V heater
  • 53HK7Compactron Booster/damper/efficiency diode + beam power pentode, 53.2 V heater

List of American RMA professional tubes

Typecode explained above

  • 1B22, 1B29, 1B31, 1B42 – Hydrogen+Argon-filled spark gaps used as pulse modulator
  • 1B23, 1B24TR cells
  • 1B25 – 160 V, 30 mA Cold-cathode surge protector
  • 1B26, 1B27 – TR cells
  • 1B32, 1B34 – Gas-filled spark gaps
  • 1B35, 1B36, 1B37, 1B38 – TR cells
  • 1B40, 1B62 – Gas-filled microwave switching tubes
  • 1B41 – 9.5 kV, 450 A Gas-filled spark gap
  • 1B43 – Gas-filled spark gap
  • 1B44 – ATR cell
  • 1B45 – 14 kV, 450 A Gas-filled spark gap
  • 1B46 (79...85 V), 1B47 (75...90 V), 1B64 (70 V) – 1...2 mA Voltage-regulator tubes, T4 metal envelope, B15d Bayonet candelabra lamp base
  • 1B48 – 2.7 kV, 50 mA Gas-filled rectifier
  • 1B49 – 12 kV, 450 A Gas-filled spark gap
  • 1B51, 1B52, 1B53, 1B54, 1B55, 1B56, 1B57, 1B58 – TR/ATR/PTR cells
  • 1B59 – 140 V, 5-35 mA Cold-cathode Glow modulator tube, modulation up to 15 kHz, 2-pin Octal base
  • 1B60, 1B63, 1B63A = WF45, 1B63B – TR cells
  • 1B67, 1B68 (β, γ), 1B69, 1B70, 1B71, 1B72, 1B73, 1B74 (Argon, γ), 1B75 (Argon, β), 1B76 (Neon, β), 1B77 (Argon, β), 1B78, 1B79 (Argon), 1B80 (Neon), 1B81 (Argon), 1B83, 1B84, 1B85 (β, γ), 1B86 (300-volts Thyrode, γ), 1B87 (γ), 1B88 (300-volts Thyrode, γ), 1B89 (X-rays, Beryllium window), 1B90 (β, γ), 1B97, 1B98, 1B99, 1B100 (Neon), 1B102 (Thyrode, β), 1B105 (Neon), 1B106 (Thyrode, β), 1B124 (Thyrode, γ) – Self-quenching radiation counter tubes
  • 1B125Thyrode Radiation counter tube for studying cosmic rays, prospecting radioactive ores from aircraft or other fast-moving vehicles, or for environmental monitoring
  • 1B126 – Needle-shaped Thyrode radiation counter used in neurosurgery to trace 123Iodine
  • 1C21 – 180 V, 25 mAavg, 100 mApeak Cold-cathode triode thyratron, 6-pin Octal base
  • 1D21 – 50 mAavg, 5 Apeak Strobotron Gas-filled, luminescent tetrode thyratron used as a stroboscope lamp
  • 1L38 = 8047 – 50 pF, 7.5 kV Vacuum capacitor
  • 1N23Silicon point contact diode used in early radar mixers
  • 1N34Germanium point contact diode[131]
  • 1P21 (S4), 1P22 (S5) – 9-stage, side-on photomultiplier, 11-pin Submagnal base
  • 1P23 – Gas-filled, side-on, S1 (red/IR-sensitive) phototube, UX4 base
  • 1P24 – High-vacuum, side-on, S4 phototube, cartridge type
  • 1P25 – S1→P1 Image converter used in World War II night vision "sniperscopes" (S1 infrared (800 nm) photocathode and P1 green Phosphor)
  • 1P26, 1P27, 1P30 – Gas-filled, side-on, S1 phototubes, UX4 base
  • 1P28 – 9-Stage, side-on, S5 photomultiplier, 11-pin Submagnal base
  • 1P29 – Gas-filled, side-on, S3 (violet/green sensitive) phototube, UX4 base; similar to 868
  • 1P31 (2 Wires with banana plugs), 1P32, 1P35 (3-pin PeeWee base), 1P33, 1P34, 1P36 (UX4 base) – Gas-filled, side-on, S1 phototubes
  • 1P37 – Gas-filled, side-on, S4 phototube, UX4 base
  • 1P39 – High-vacuum, side-on, S4 phototube, 5-pin Octal base; 929 with a non-hygroscopic 5-pin base
  • 1P40 – Gas-filled, side-on, S1 phototube, 5-pin Octal base; 930 with a non-hygroscopic base
  • 1P41 – 924 Gas-filled, head-on, S1 phototube with a 3-pin PeeWee base
  • 1P42 – High-vacuum, head-on, S9, coaxial phototube
  • 1Q21 – 9.2-9.3 GHz Tunable reference cavity
  • 1Q22 (9.25 GHz), 1Q23 (9.28 GHz), 1Q24 (9.31 GHz), 1Q25 (9.375 GHz), 1Q26, 1Q26A (9.28 GHz Beacon) – Reference cavities
  • 1R21 – 9 kV, 400 A Ignitron
  • 1S22 – 10 kV, 20 A Vacuum SPDT switch actuated by a lever extending through a flexible Kovar diaphragm
  • 2A21 (6.5-9.5 V/1 A), 2A22 (3-8 V/1.7 A) – Ballast tubes, Octal base
  • 2B22 – 1.5 GHz Lighthouse-type Disk-seal diode, 6.3 V/750 mA heater, Octal base
  • 2B23 – Indirectly heated, magnetically controlled diode. An external, variable magnetic field from a solenoid spirals the electron stream away from the anode like in a Magnetron, driving the tube into cut-off with a sensitivity of -2 mA/G (-20 mA/mT), 6.3 V/300 mA heater, Octal base[132]
  • 2B25 – 2.8 kV, 1.5 mA Half-wave rectifier, 1.4 V/110 mA filament, Miniature 7-pin base
  • 2B35/EA50 – Subminiature video detector diode, 6.3 V/150 mA heater, 3+1-pin all-glass with anode on top pin
  • 2C21 = 1642 – Separate cathodes dual RF triode, 6.3 V/600 mA heater, Micanol U7A base, one grid on top cap
  • 2C22 = 7193 – 3.3 W VHF Power triode, 6.3 V/300 mA heater, Octal base, grid and anode on separate top caps
  • 2C26, 2C26A (Pulse-rated) – 10 W, 300 MHz Power triode, 6.3 V/1.1 A heater, Octal base, grid and anode on separate top caps
  • 2C33 – 1.25 kV, 25 mAavg, 1.5 Apeak Argon-filled tetrode thyratron, negative starter voltage, 2.5 V/2.5 A filament, Octal base
  • 2C34 – 2×5 W, 80 MHz Dual power triode, 6.3 V/600 mA heater, Octal base with two anode top caps
  • 2C36 – 1.75 GHz Rocket-type Disk-seal triode with an internal feedback circuit between cathode and anode used as UHF oscillator, 6.3 V/400 mA heater
  • 2C37 – 3.3 GHz Rocket triode used as SHF oscillator, 6.3 V/400 mA heater
  • 2C38, 2C39 (Glass/metal), 2C39A, 2C39B, 2C39BA = TD1-100C = EC562 (ceramic/metal) – 100 W, 3 GHz Oil can-type Forced-air cooled disk-seal power triode, 4.5-6.3 V/1.03 A heater; ruggedized version: 2C39-WA
  • 2C40, 2C40A – 6.5 W, 3.37 GHz Lighthouse-type Disk-seal power triode for CW operation, 6.3 V/750 mA heater, Octal base
  • 2C41 – 2.2 kWpeak, 3 GHz Oil can-type Pulse-rated power triode, 6.3 V/1.03 A heater
  • 2C42 – 1750 Wpeak, 1050 MHz Lighthouse-type Pulse-rated power triode, 6.3 V/900 mA heater, 6-pin Octal base; upgraded 446
  • 2C43 – 12 W, 1.5 GHz Lighthouse-type Pulse-rated power triode, 6.3 V/800 mA heater, 6-pin Octal base
  • 2C46 – 12 W, 1.3 GHz Lighthouse-type Power triode, 6.3 V/750 mA heater, 6-pin Octal base
  • 2C50 – Separate cathodes dual triode used in servo amplifiers, 12.6 V/300 mA heater, Octal base
  • 2C51 – Dual separate cathodes, shielded, medium-μ VHF triode, 6.3 V/300 mA heater, Noval base
  • 2C52 – Separate cathodes, low-drift, dual triode used as precision DC amplifier, 12.6 V/300 mA heater, Octal base
  • 2C53 – 12 W, 8 kV Power triode used as 5 mA shunt regulator, 6.3 V/300 mA heater, Octal base with anode on top cap
  • 2D21/EN91 = Philips PL21 = PL2D21 = STC 4G/280K – 650 V, 100 mAavg, 500 mApeak, 10 Asurge, Xenon-filled tetrode thyratron used as relay driver or grid-controlled rectifier, mostly in jukeboxes and computer equipment, negative starter voltage, 6.3 V/600 mA heater, Miniature 7-pin base; ruggedized versions: 2D21-W/5727/E91N, CV797
  • 2E22 – 30 W RF Power pentode, 6.3 V/1.5 A heater, UY5 base with anode on top cap
  • 2E24 – 10 W, 125 MHz Beam power tetrode, center-tapped 6.3 V/650 mA filament, Micanol Octal base
  • 2E25 – 15 W, 100 MHz Beam power tetrode, 6.3 V/1 A thoriated Tungsten quickstart filament, Octal base
  • 2E26 – 5.3 W, 175 MHz Beam power tetrode, 6.3 V/800 mA heater, Octal base, popular among radio amateurs
  • 2E30 – 10 W, 165 MHz Beam power tetrode with deflection screens available on separate pin, 6.3 V/650 mA quickstart filament, Miniature 7-pin base
  • 2E31 (Long wire-ends), 2E32 (short wire-ends for use with a socket) – Subminiature, low (22.5-45 V) anode voltage, fully shielded sharp-cutoff RF/IF pentode, 1.25 V/50 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 2E35 (Long wire-ends), 2E36 (short wire-ends) – 6 mW Subminiature, low (22.5-45 V) anode voltage power pentode, 1.25 V/30 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 2E41 (Long wire-ends), 2E42 (short wire-ends) – Subminiature, low (22.5-45 V) anode voltage diode + pentode, 1.25 V/30 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 2F21 – Hexode-type monoscope, Indian Head test pattern, 6.3 V/600 mA heater, U6A base with dual top caps for #4 grid and anode
  • 2G21 (Long wire-ends), 2G22 (short wire-ends) – Subminiature, low (22.5-45 V) anode voltage triode/heptode oscillator/mixer, 1.25 V/50 mA filament, all-glass elliptical cross-section envelope with 7 inline wire-ends
  • 2H21Phasitron, a magnetically controlled beam deflection phase modulator tube used in early FM broadcast transmitters, 6.3 V/300 mA heater, Magnal 11-pin base;[133] superseded by 5593[134][135][136]
  • 2J21 – 10 kW, 9.345-9.405 GHz Forced-air cooled, pulsed Magnetron, 6.3 V/1.2-1.4 A heater
  • 2J22 (3.45-3.55 GHz), 2J23 (3.071-3.1 GHz), 2J24 (3.047-3.071 GHz), 2J25 (3.019-3.047 GHz), 2J26 (2.992-3.01 GHz), 2J27 (2.965-2.992 GHz), 2J28 (2.939-2.965 GHz), 2J29 (2.914-2.939 GHz), 2J30 (2.86-2.9 GHz), 2J31 (2.82-2.86 GHz), 2J32 (2.78-2.82 GHz), 2J33 (2.74-2.78 GHz), 2J34 (2.7-2.74 GHz) – 240 W Forced-air cooled, pulsed Magnetrons, 6.3 V/1.5 A heater
  • 2J35 – 1 W, 3 GHz Magnetron, 1.8 V/2 A heater, glass envelope, UX4 base
  • 2J36 – 12 W, 9.003-9.168 GHz Pulsed Magnetron, 6.3 V/1.3 A heater
  • 2J37 – 80 W, 3.267-3.277 GHz Pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J38 – 10 W, 3.249-3.263 GHz Pulsed Magnetron, 6.3 V/1.25 A heater
  • 2J39 – 12 W, 3.267-3.355 GHz Pulsed Magnetron, 6.3 V/1.25 A heater
  • 2J40 – 10 W, 9.305-9.325 GHz Pulsed Magnetron, 6.3 V/1.3 A heater
  • 2J42 – 7 kW, 9.345-9.405 GHz Forced-air cooled, pulsed Magnetron, 6.3 V/600 mA heater
  • 2J49 (9-9.16 GHz), 2J50 (8.75-8.9 GHz) – 40 kW Pulsed Magnetrons, 6.3 V/1 A heater
  • 2J51, 2J51A – 50 kW, 8.5-8.96 GHz Pulsed Magnetron, 6.3 V/0.9-1 A heater
  • 2J54 – 38 kW, 3.123-3.259 GHz Forced-air cooled, pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J55 (9.345-9.405 GHz), 2J56 (9.225-9.265 GHz) – 40 kW Pulsed Magnetrons used as pulsed oscillator, 6.3 V/1 A heater[137]
  • 2J58 – 60 W, 2.965-3.019 GHz Pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J59 – 50 W, 3.236-3.276 GHz Pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J61A – 60 W, 2.995-3.105 GHz Pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J62A – 60 W, 2.912-3.022 GHz Pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J64 – 600 W, 1.4 GHz Pulsed Magnetron, 6.3 V/1.3 A heater
  • 2J66 (2.845-2.905 GHz), 2J67 (2.795-2.855 GHz), 2J68 (2.745-2.805 GHz), 2J69 (2.695-2.755 GHz) – 150 W Pulsed Magnetron, 6.3 V/1.5 A heater
  • 2J70 – 20 kW, 3.03-3.11 GHz Forced-air cooled, pulsed Magnetron, 6.3 V/1.1-1.4 A heater
  • 2K25 – 20 mW, 8.5-9.66 GHz Reflex Klystron, 6.3 V/440 mA heater
  • 2K26 – 80 mW, 6.25-7.06 GHz Reflex Klystron, 6.3 V/440 mA heater, 4-pin Octal base
  • 2K29 – 100 mW, 3.4-3.96 GHz Reflex Klystron, 6.3 V/440 mA heater, modified Octal base
  • 2K31 – 3 W, 2.7-3.3 GHz 2-Cavity Klystron, 6.3 V/1.3 A heater, Octal base
  • 2K33 – 20 mW, 23-25 GHz Reflex Klystron, 6.3 V/650 mA heater, 4-pin Octal base
  • 2K34 (18 W), 2K35 (30 W) – 2.73-3.33 GHz 3-Cavity Klystrons, 6.3 V/1.5 A heater, Octal base
  • 2K39 (7.5-10.3 GHz), 2K41 (2.66-3.31 GHz), 2K42 (3.3-4.2 GHz), 2K43 (4.2-5.7 GHz), 2K44 (5.7-7.5 GHz) – 250 mW Reflex Klystrons, 6.3 V/1.3 A heater
  • 2K40 – 30 mW, 5-10 GHz Reflex Klystron, 6.3 V/330-390 mA heater, 3-pin PeeWee base
  • 2K45 – 30 mW, 8.5-9.66 GHz Reflex Klystron with thermal tuning - one wall of the cavity is also the anode of a triode, so increasing the triode current results in thermal expansion of that wall, altering the cavity geometry, 6.3 V/760 mA heater
  • 2K50 – 15 mW, 23.5-24.5 GHz Reflex Klystron, 6.3 V/705...805 mA heater, Octal base
  • 2K51 (2.7-3.3 GHz), 2K52 (2.9-3.7 GHz), 2K53 (3.2-4 GHz) – 2-Cavity Klystrons, 6.3 V/1.4 A heater, Octal base
  • 2K56 – 3.84-4.46 GHz Reflex Klystron, 6.3 V/440 mA heater, Octal base
  • 2K57 – 4.82-5.12 GHz Reflex Klystron, 6.3 V/1.5 A heater, Octal base
  • 2P21, 2P22, 2P23 – Early Image Orthicon video camera tubes, 6.3 V/600 mA heater, Diheptal 14-pin base
  • 3B21 (Argon-filled, Graphite anode), 3B22 (Xenon-filled, Tantalum anode) – 725 V, 1.25 Aavg, 5 Apeak Half-wave rectifiers, 2.5 V/6 A filament, UX4 Bayonet base
  • 3B23 – 3.5 kV, 2×600 mA Full-wave rectifier, half-indirect 2.5 V/8 A heater, UX4 Bayonet base with dual anode top cap
  • 3B24 = Western Electric 732A – 20 kV, 60 mAavg, 300 mApeak Half-wave rectifier, center-tapped 2.5 V/6 A resp. 5 V/3 A filament, UX4 Bayonet base with anode on top cap; ruggedized versions: 3B24-W, 3B24-WA
  • 3B25 – 4.5 kV, 500 mAavg, 2 Apeak Gas-filled half-wave rectifier, 2.5 V/5 A filament, UX4 Bayonet base with anode on top cap
  • 3B26 – 15 kV, 20 mAavg, 8 Apeak Ruggedized, Nonex hard glass clipper diode, half-indirect 2.5 V/4.75 A heater, Octal base with anode on top cap
  • 3B27 – 8.5 kV, 150 mAavg, 600 mApeak Half-wave rectifier, split-cathode half-indirect 2.5 V/5 A heater, UX4 Bayonet base with anode on top cap
  • 3B28 – 10 kV, 250 mAavg, 1 Apeak Xenon-filled half-wave rectifier, 2.5 V/5 A filament, UX4 Bayonet base with anode on top cap; ruggedized replacement for Mercury-vapor type 866
  • 3B29 – 16 kV, 64 mAavg, 250 mApeak Ruggedized, Nonex hard glass clipper diode, half-indirect 2.5 V/4.9 A heater, UX4 Bayonet base with anode on top cap
  • 3C22 – 125 W, 1.4 GHz Forced-air cooled, disk-seal power triode, 6.3 V/2 A heater, Octal base
  • 3C23 – 1.25 kV, 1.5 Aavg, 6 Apeak Argon/Mercury-vapor triode thyratron, 2.5 V/7 A filament, UX4 Bayonet base with anode on top cap
  • 3C24 (Grid on side pin), 3C28 (grid on dual side pin), 3C34 (grid on base pin) – 25 W, 60 MHz Power triodes, 6.3 V/3 A filament, ceramic UX4 Bayonet base with anode on top pin
  • 3C27B, 3C37 – 10 kWpeak, 1.15 GHz Pulse-rated, coaxial power triodes, 6.3 V/2.5 A heater
  • 3C33 – ±2 kV, 2×15 W Common cathode dual power triode used in burst- or phase-fired controllers, 12.6 V/1.125 A heater, Septar base
  • 3C36 – 500 W, 1.5 GHz Water-cooled disk-seal power triode, 6.3 V/2.8 A heater
  • 3C45 = 6130 – 3 kV, 45 mAavg, 1.5 ARMS, 35 Apeak Hydrogen triode thyratron, positive control characteristic, half-indirect 6.3 V/2-2.5 A heater, Micanol UX4 base with anode on top cap; ruggedized version: 3C45-W
  • 3D21, 3D21A, 3D21B – 5 kV, 15 W Pulse-rated beam power tetrode, center-tapped 12.6 V/850 mA resp. 6.3 V/1.7 A indirect heater, Octal base with anode on top cap; ruggedized version: 3D21-WB
  • 3D22 = STC 4G/401A, 3D22A – 650 V, 800 mAavg, 8 Apeak Gas-filled, tetrode thyratron, 6.3 V/2.5 A filament, B7D/U7G Giant 7-pin base
  • 3D23 – 35 W RF Power tetrode, 6.3 V/3 A filament, ceramic UX4 Bayonet base with anode on top cap
  • 3D24 – 45 W, 125 MHz Power tetrode, 6.3 V/3 A filament, Loctal base with anode on top cap
  • 3E22 – 815 Dual beam power tetrode with a Micanol Octal base
  • 3E29 – Pulse-rated 829B dual beam power tetrode used in radar equipment
  • 3J21 – 150 W, 23.746-24.226 GHz Magnetron, 12.6 V/1.6 A heater
  • 3J22 – 80 W, 4.3-4.95 GHz Pulsed Magnetron, 6.3 V/1.5 A heater
  • 3J31 – 40 kW, 23.792-24.176 GHz Pulsed Magnetron, 6 V/1.7-2.1 A heater
  • 3K21 (2.3-2.725 GHz), 3K22 (3.3-4 GHz), 3K30 (2.7-3.3 GHz) – 40 W, 2-Cavity Klystrons, Octal base
  • 3K23 (5 W, 950-1150 MHz), 3K27 (3 W, 750-960 MHz) – Reflex Klystrons, 6.3 V/1.5 A heater, Octal base
  • 4A21 – 11-15 V/1.59-1.65 A Ballast tube, Octal base
  • 4B22 = EL5B – 340 V, 5 A Argon-filled full-wave rectifier, 2.5 V/11-13 A filament, E39 Mogul Edison screw lamp base with Graphite anodes on top pins
  • 4B23 = EL5BHD – 425 V, 5 A Heavy-duty Argon-filled full-wave rectifier, 2.5 V/16-18 A filament, E39 Mogul Edison screw lamp base with Graphite anodes on top pins
  • 4B24 = EL3C – 725 V, 2.5 A Argon-filled full-wave rectifier with Graphite anodes, 2.5 V/10.5-12.5 A filament, 4-pin base
  • 4B25 = EL6CF – 725 V, 6.4 A Argon-filled full-wave rectifier with Graphite anodes, 2.5 V/16-18 A filament, 4-pin base
  • 4B26 = 2000 – 375 V, 6 A Gas-filled half-wave rectifier, 2.2 V/18 A filament, E39 Mogul Edison screw lamp base with anode on top pin
  • 4B27 – 1 kV, 2 A Gas-filled full-wave rectifier, 2.5 V/10 A filament, 4-pin base
  • 4B28 – 300 V, 6 A Gas-filled half-wave rectifier, 2.2 V/17 A filament, E39 Mogul Edison screw lamp base with anode on top pin
  • 4B31 – 15 kV, 60 mA Half-wave rectifier, half-indirect 5 VAC/5 A heater, B4D Superjumbo base with anode on top cap
  • 4B32 = STC 2G/472B – 10 kV, 1.25 Aavg, 5 Apeak Xenon-filled half-wave rectifier, 5 V/7.25 A filament, B4F/U4J Jumbo base with anode on top cap
  • 4B35 (90 V, 3 A), 4B36 (275 V, 2 A) – Tungar-type Gas-filled half-wave rectifier, 2 V/12 A filament, E39 Mogul Edison screw lamp base
  • 4C21 – 100 W, 1 MHz Power triode, 10 V/3.25 A filament, B4F/U4J Jumbo base
  • 4C25 – 50 W, 30 MHz Power triode, 5 V/5 A filament, UX4 base
  • 4C27 = 8026 – 150 W, 600 MHz Coaxial power triode, 6 V/6.5 A filament
  • 4C28 – 7.5 kV, 2 A Pulse modulator power triode used in small LORAN and SHORAN transmitters, 6 V/6.5 A filament
  • 4C29 – 150 W Pulse-rated UHF power triode, 6 V/6.5 A filament
  • 4C32 – 200 W, 60 MHz Power triode used in shortwave diathermy generators, 10 V/4.5 A filament
  • 4C33 – 250 W, 625 MHz Forced-air cooled, pulse-rated power triode, 5 V/9.1 A heater
  • 4C34 – 250 W, 60 MHz Power triode, 11 V/4 A filament
  • 4C35 = Philips PL435 = Toshiba 1G35P, 4C35A – 8 kV, 100 mAavg, 90 Apeak Hydrogen thyratron, 6.3 V/5.5-6.7 A heater, B4D Superjumbo base with anode on top cap
  • 4C36 – 125 W, 60 MHz Power triode, 5 V/7.5 A filament, B4F/U4J Jumbo base
  • 4D21 = 6155 = Eimac 4-125A – 125 W Glass VHF beam power tetrode, 5 V/6.5 A filament, B5E Giant 5-pin UY base with metal shell and anode on top cap
  • 4D22 (Center-tapped 25.2 V/800 mA resp. 12.6 V/1.6 A heater), 4D32 (6.3 V/3.75 A heater) – 50 W, 60 MHz Beam power tetrodes, Septar base with anode on top cap
  • 4D23 – 150 W, 120 MHz Beam power tetrode, 5 V/7.5 A filament, B5D/U5G Giant 5-pin UY base
  • 4E27/8001 (75 W), 4E27A/5-125B (85 W) – Glass radial-beam power pentode, 5 V/7.5 A filament, B7D/U7G Giant 7-pin base with anode on top pin
  • 4J21 (1336-1350 MHz), 4J22 (1322-1336 MHz), 4J23 (1308-1322 MHz), 4J24 (1294-1308 MHz), 4J25 (1280-1294 MHz) – 640 kW Pulsed Magnetrons, 20.5 V/2.2 A heater
  • 4J26 (1268-1280 MHz), 4J27 (1256-1268 MHz), 4J28 (1244-1256 MHz), 4J29 (1232-1244 MHz), 4J30 (1220-1232 MHz) – 700 kW Pulsed Magnetrons, 23.5 V/2.2 A heater
  • 4J31 (2.86-2.90 GHz), 4J32 (2.82-2.86 GHz), 4J33 (2.78-2.82 GHz), 4J34 (2.74-2.78 GHz), 4J35 (2.70-2.74 GHz), 4J36 (3.65-3.70 GHz), 4J37 (3.60-3.65 GHz), 4J38 (3.55-3.60 GHz), 4J39 (3.50-3.55 GHz), 4J40 (3.45-3.50 GHz), 4J41 (3.4-3.45 GHz) – 1 MWpeak, 1 kWavg Pulsed Magnetrons, 16 V/3.1 A heater
  • 4J42 – 40 kW, 660-730 MHz Magnetron[138]: 287ff 
  • 4J43 (2.992-3.019 GHz), 4J44 (2.965-2.992 GHz) – 750 kW Pulsed Magnetrons, 16 V/3.1 A heater
  • 4J50, 4J50TO = CSF F1005, 4J50TR = F1103 – 8.3-9.6 GHz Forced-air cooled Magnetron, 13.75 V/3.5 A heater
  • 4J52 (12.6 V/2.1 A heater), 4J52A (12.6 V/2.2 A heater), 4J52T (ruggedized) – 200 kW, 9.345-9.405 GHz Forced-air cooled, pulsed Magnetrons
  • 4J53 – 750 kW, 2.793-2.813 GHz Pulsed Magnetron, 16 V/3.1 A heater
  • 4J54 (6.775-6.875 GHz), 4J55 (6.675-6.775 GHz), 4J56 (6.575-6.675 GHz), 4J57 (6.475-6.575 GHz), 4J58 (6.375-6.475 GHz), 4J59 (6.375-6.275 GHz) – 250 kW Pulsed Magnetrons, 12.6 V/3.25-4 A heater
  • 4J70 (3.54-3.71 GHz), 4J71 (3.39-3.56 GHz), 4J72 (3.24-3.41 GHz), 4J73 (3.09-3.26 GHz) – 350 Wavg Pulsed Magnetrons, 16 V/2.8-3.4 A heater
  • 4J74 (2.99-3.11 GHz), 4J75 (2.89-3.01 GHz), 4J76 (2.79-2.91 GHz), 4J77 (2.69-2.81 GHz) – 450 Wavg Pulsed Magnetrons, 16 V/2.8-3.4 A heater
  • 4J78 – 4J50 with a 9.03-9.168 GHz range
  • 5B21 – 225 V, 15 A Gas-filled half-wave rectifier, 2.5 V/25 A filament, E39 Mogul Edison screw lamp base
  • 5B24 – 1 kV Full-wave, Mercury-vapor Tungar bulb, a low-voltage rectifier for charging 60-cell lead-acid batteries at 6 A, 2.5 V/18 A filament[139]
  • 5C21 = C6J – 750 V, 6.4 A Xenon-filled triode thyratron with negative control voltage, 2.5 V/21 A heater, B4D Superjumbo base
  • 5C22/6279, 5C22A – 16 kV, 200 mAavg, 325 Apeak Hydrogen triode thyratron used in radar modulators, half-indirect 6.3 V/9.6-11.6 A heater, B4D Superjumbo base with anode on top cap
  • 5C30 – 750 V, 5 A Triode thyratron with negative control voltage, 2.5 V/23 A heater, E39 Mogul Edison screw lamp base
  • 5D21 – 60 W Beam power tetrode, 26 V/2.1 A heater, B4A Ventilated 4-pin base with anode on top terminal
  • 5D22/6156/4-250A – 250 W, 110 MHz Glass beam power tetrode, 5 V/14.5 A filament, B5E Giant 5-pin UY base with anode on top cap
  • 5D23 – 140 W, 45 MHz Power tetrode, 5 V/14.5 A filament, B4F/U4J Jumbo base
  • 5J21 (1198-1110 MHz), 5J22 (1186-1198 MHz), 5J23 (1074-1186 MHz), 5J24 (1062-1074 MHz), 5J25 (1050-1062 MHz) – 250 kW Pulsed Magnetrons, 20.5 V/3.4 A heater
  • 5J26 – 500 kW, 1.22-1.35 GHz Forced-air cooled Magnetrons, 23.5 V/2.2 A heater
  • 5J29 (165 W, 375-770 MHz), 5J30 (200 W, 10-375 MHz), 5J32 (200 W, 90-450 MHz), 5J33 (260 W, 750-1150 MHz) – Magnetrons, 2.1 V/40 A heater
  • 6B21 – 100 kV, 100 mA Half-wave rectifier, 5 VAC/24 A filament, B4F/U4J Jumbo base with anode on top cap
  • 6C21 – Pulse-rated power triode used in hard-tube pulser radar modulators, 8.2 VAC/17 A filament, B4F/U4J Jumbo base
  • 6C23 – 1 kW, 600 MHz Forced-air cooled, pulse-rated power triode, 2-phase, common center-tapped 7 V/((1+j)×12...14 A) heater
  • 6C24 – 600 W Forced-air cooled power triode, center-tapped 11 V/12.1 A filament
  • 6D21 – Pulse-rated power tetrode used in hard-tube pulser radar modulators, 7.5 V/20 A filament, B5D/U5G Giant 5-pin UY base
  • 6J21 – 800 W, 2.5-3.55 GHz Forced-air cooled Magnetron, 5.6 V/17.2 A heater
  • 7C23 – 17.5 kV, 120 kWpeak, 1.2 kWavg, 5 MHz Pulse power triode, center-tapped 11 V/29 A filament
  • 7C24/5762 = RCA 4654 – 4 kW, 30 MHz Forced-air cooled power triode, center-tapped 12.6 V/29 A filament
  • 7C25 – 2.5 kW, 30 MHz Power triode, center-tapped 11 V/28 A filament
  • 7C26 – 1 kW, 150 MHz Power triode, center-tapped 9 V/28 A filament
  • 7C27 – 3 kW, 110 MHz Power triode, center-tapped 16 V/28.5 A filament
  • 7C30 – 3 kW, 1.6 MHz Power triode, center-tapped 16 V/28.5 A filament
  • 8C22 – 1 kW, 400 MHz Forced-air cooled, pulse-rated power triode, 4.1 V/296...344 A filament
  • 8C23 – 1 kW, 600 MHz Forced-air cooled, pulse-rated power triode, 4.1 V/296...344 A filament
  • 8D21 – 2×3 kW, 216 MHz Internally water-cooled dual power tetrode used in early VHF TV transmitters, 3.2 V/125 A filament
  • 9C21 (Water+forced-air-cooled, 40 kW), 9C22 (Forced-air cooled, 20 kW) – Power triodes, 19.5 V/415 A filament, 4-pin base and flanged-header grid terminal around the tube
  • 9C24 – 5 kW, 220 MHz Water-cooled, ceramic/metal VHF power triode used in grounded-grid amplifiers, 6.3 V/240 A filament; superseded by 6039
  • 9C25 – 11.5 kW, 30 MHz Forced-air cooled beam power tetrode, 6.0 V/285 A filament, 2-pin base and flanged-header grid terminal
  • 9C26 – 7.5 kW Forced-air cooled power triode, 6.0 V/285 A filament, 2-pin base and flanged-header grid terminal
  • 9C27 – 25 kW, 30 MHz Water+forced-air cooled power triode, 6.0 V/285 A filament, 2-pin base and flanged-header grid terminal

List of American EIA professional tubes

Many of these are special quality versions of the equivalents given. Some manufacturers preceded the EIA number with a manufacturer's code, as explained above

LoVTList of American EIA professional tubes

5000s

  • 5512 – 25 kW, 110 MHz Water-cooled, coaxial power triode with integral water jacket, 6.2 V/435 A filament
  • 5513 – 1.2 kW, 220 MHz Forced-air cooled, glass/metal, coaxial power triode, 6.3 V/30 A filament
  • 5514 – 65 W RF Power triode with a Zirconium-coated Graphite anode on top cap, 7.5 V/3 A filament, UX4 base
  • 5516 – 15 W, 80 MHz Beam power pentode, Zirconium-coated anode on top cap, Gold-coated control grid, "carbonized" screen grid, center-tapped 6 V/700 mA oxide-coated quickstart filament, Micanol Octal base
  • 5517 – 2.8 kV, 12 mA Gas-filled, cold-cathode, triggerable half-wave rectifier used in photoflash power supplies, Miniature 7-pin base with anode on top cap
  • 5518 – 4 kW, 110 MHz Forced-air cooled, glass/metal, coaxial power triode, 6.3 V/235 A filament
  • 5519, 5520, 5521, 5522, 5523, 5532, 5533, 5534, 5535, 5536, 5537, 5538, 5539, 5540, 5599, 5600, 5601, 5602X-ray tubes
  • 5527 – 2" (5.1 cm) Iconoscope, 6.3 V/600 mA heater, Diheptal 12-pin base
  • 5528 – 500 V, 6.4 A Xenon-filled triode thyratron, 2.5 V/21 A filament, 4-pin base with anode on top cap
  • 5530 (110 MHz), 5530H (30 MHz) – 4 kW Forced-air power triode, 5 V/55 A filament
  • 5531 – 10 kW, 30 MHz Forced-air cooled power triode, 5.3 V/92 A filament
  • 5541 – 10 kW, 110 MHz Forced-air cooled power triode, 7.3 V/57 A filament
  • 5545 = STC 3G/501A – 1.5 kV, 6.4 A Gas-filled triode thyratron, 2.5 V/21 A filament, B4D Superjumbo base with anode on top cap
  • 5549 – 4 kW, 50 MHz Forced-air cooled power triode, 12.6 V/57 A filament
  • 5550 (Size A), 5551, 5551A (size B, water-cooled), 5552A (size C), 5553B (size D), 5554, 5555 – Ignitrons
  • 5556 – 10 W, 6 MHz Power triode, 4.5 V/1.1 A filament, UX4 Bayonet base
  • 5557 – 2 kV, 500 mA Mercury-vapor triode thyratron, negative control characteristic, 2.5 V/5 A filament, UX4 Bayonet base with anode on top cap
  • 5558 – 5 kV, 2.5 A Mercury-vapor half-wave rectifier, half-indirect 5 V/4.5 A heater, UX4 Bayonet base with anode on top cap
  • 5559 – 1 kV, 2.5 A Mercury-vapor triode thyratron, half-indirect 5 V/4.5 A heater, UX4 Bayonet base with anode on top cap
  • 5560 – 1 kV, 2.5 A Mercury-vapor tetrode thyratron, half-indirect 5 V/4.5 A heater, UX4 Bayonet base with anode on top cap
  • 5561 – 3 kV, 6.4 A Mercury-vapor, half-wave rectifier, 5 V/10 A heater, B4D Superjumbo base with anode on top cap
  • 5563 (10 kV), 5563A (15 kV) – 1.8 A Mercury-vapor triode thyratron with a negative control characteristic, 5 V/10 A heater, B4F/U4J Jumbo base with anode on top cap
  • 5575/100 (20 V/24 A filament, 1 A anode current), 5576/200 (20 V/32 A filament, 2.5 A) – 150 kV Radiation-cooled half-wave rectifier
  • 5581 (5-pin Octal base), 5582 (Cartridge-type), 5583 (3-pin PeeWee base) – Gas-filled, side-on, S4 (blue-sensitive) phototubes
  • 5584 – Dual gas-filled, side-on, S4 phototube, UX4 base
  • 5586 (2.7-2.9 GHz), 5657 (2.9-3.1 GHz) – 1.2 kW Pulsed Magnetrons, 16.0 V/2.8-3.4 A heater
  • 5588 – 200 W, 1 GHz Forced-air cooled, coaxial power triode, half-indirect 6.3 V/2.5 A heater; superseded by 6161
  • 5589 = Western Electric 376B – 275 V, 20 mA (10000h lifespan) or 35 mA (1000h lifespan) Gas-filled cold-cathode trigger triode, 6-pin Octal base
  • 5590 = Western Electric 401A (Long-life 6AK5/EF95), 5591 = 403B – VHF Pentodes, 6.3 V/150 mA heater, Miniature 7-pin base
  • 5592 – Forced-air cooled power triode, 11 V/412 A heater, special 4-pin base
  • 5593Phasitron, a magnetically controlled beam deflection phase modulator tube used in early FM broadcast transmitters, 6.3 V/300 mA heater, Magnal 11-pin base;[140] derived from the 2H21[134][135][136]
  • 5594 – 5 kV, 500 mA Gas-filled triode thyratron, 2.5 V/5 A filament, UX4 Bayonet base
  • 5603 = Western Electric 398A – Power pentode, 6.3 V/500 mA filament, Octal base
  • 5604, 5604A (Forced-air cooled, 10 kW), 5619 (water-cooled, 20 kW) – 25 MHz Power triode, 11 V/176 A filament
  • 5607 – 1 kW, 2.5-3.55 GHz Water+forced-air cooled Magnetron, 5.6 V/17.2 A filament
  • 5608 – 5.5 W Dual power triode designed for use with AC anode voltage and critical grid leak requirements, 2.5 V/2 A heater, U7A base
  • 5609 – 80 W, 2.425-2.475 GHz Forced-air cooled Magnetron used for microwave dielectric heating, 6.3 V/3.8 A heater
  • 5610 – Triode, 6.3 V/150 mA heater, Miniature 7-pin base
  • 5612, 5613 (2 Wires with banana plugs), 5614, 5615, 5616, 5617 (UX4 base) – Gas-filled, side-on, S4 phototubes
  • 5618 – VHF Power pentode, center-tapped 6 V/230 mA resp. 3 V/460 mA heater, Miniature 7-pin base
  • 5632 = EEV C3J = ELC3J – 1.25 kV, 2.5 A Xenon-filled triode thyratron with negative control characteristic, center-tapped 2.5 V/9 A heater, UX4 Bayonet base with anode on top cap
  • 5633 – Subminiature, remote-cutoff RF pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, chaotic 6-pin/wire-ends
  • 5634 – Subminiature, sharp-cutoff RF pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, chaotic 6-pin/wire-ends
  • 5635 – Subminiature, common-cathode dual triode, 6.3 V/450 mA heater, all-glass round cross-section E8-10 envelope, circular 8-pin/wire-ends
  • 5636/EF730 – Ruggedized, subminiature, dual-control, sharp-cutoff pentode, 6.3 V/150 mA heater, all-glass round cross-section E8-10 envelope, circular 8-pin/wire-ends
  • 5637 – Subminiature, high-μ triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, chaotic 5-pin/wire-ends
  • 5638 – Subminiature, sharp-cutoff pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, chaotic 6-pin/wire-ends
  • 5639, 5639-WA – Ruggedized, subminiature power pentode used as CRT cathode driver, 6.3 V/450 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5640 – Subminiature beam power tetrode, 6.3 V/450 mA heater, all-glass round cross-section E8-10 envelope, 6-pin/wire-ends
  • 5641 – Ruggedized, subminiature half-wave rectifier, 6.3 V/450 mA heater, all-glass round cross-section E8-10 envelope, circular 8-pin/wire-ends
  • 5642 – Subminiature half-wave rectifier, 1.25 V/200 mA filament, all-glass envelope, 3-pin/wire-ends
  • 5643 – Subminiature Xenon-filled tetrode thyratron with negative control characteristic, 6.3 V/150 mA heater, all-glass round cross-section E8-10 envelope, circular 8-pin/wire-ends; similar to 5696/EN92, 546
  • 5644 – Subminiature 95 V voltage-regulator tube, all-glass round cross-section E8-10 envelope, circular 8-pin/wire-ends
  • 5645 – Subminiature, medium-μ triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, round 5-pin/wire-ends
  • 5646 – Subminiature, high-μ triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, round 5-pin/wire-ends
  • 5647 – Ruggedized, subminiature diode, 6.3 V/150 mA heater, 4-pin/wire-ends
  • 5648 – 100 W, 2.5 GHz Lighthouse-type Power triode, 6.3 V/1.1 A heater
  • 5649, 5650 = 5981 – 1.3 GHz Reflex Klystrons
  • 5651 = Cerberus SR54, 5651A, 5651-WA
    5651
    – 86 V Voltage-regulator tube, Miniature 7-pin base; ruggedized version: 5651-WA
  • 5652 (For AC use with balancing capacitor), 5653 (for DC use) – High-vacuum, side-on, S4 phototubes, 5-pin Octal base
  • 5654/6096/6AK5-W/E95F, CV4010 – Avionics version of 6AK5/EF95 sharp-cutoff pentode, popular in vintage radar IF amplifiers; 20 V/50 mA heater version: Western Electric 6028/408A
  • 5655 – 1.6" Image Orthicon, magnetic focus and deflection, 6.3 V/600 mA heater, Diheptal 14-pin base
  • 5656 – 2×3 W, 400 MHz Dual power tetrode, 6.3 V/400 mA heater, Noval base
  • 5657 – See 5586
  • 5658 – Upgraded drop-in replacement for the 880 power triode used for industrial, RF dielectric heating
  • 5659 – Ruggedized 12A6 beam power tetrode
  • 5660 – Ruggedized 12C8 dual diode + pentode
  • 5661 – Ruggedized 12SK7 pentode
  • 5662 – 2.25 A Triode thyratron for electric blanket controllers, 6.3 V/150 mA heater, Miniature 7-pin base
  • 5663 – Tetrode thyratron, 6.3 V/150 mA heater, Miniature 7-pin base; similar to 5696/EN92, 546
  • 5664 = EEV ELC1B/A – 1.25 kV, 1 A Xenon-filled triode thyratron with a Tantalum anode, 2.5 V/6.3 A filament, UX4 Bayonet base with anode on top cap
  • 5665 = EEV C16J – 1.25 kV, 16 A Xenon-filled triode thyratron with negative control characteristic, 2.5 V/31 A filament
  • 5666 (Water-cooled, 12.5 kW), 5667 (forced-air cooled, 7.5 kW) – Upgraded replacements for the 889A, 889RA power triodes used for industrial, RF dielectric heating
  • 5668 (Water-cooled, 20 kW), 5669 (forced-air cooled, 10 kW) – Upgraded replacements for the 892, 892R power triodes used for industrial, RF dielectric heating
  • 5670 – 800 MHz Dual medium-μ triode with separate cathodes, 6.3 V/350 mA heater, Noval base; avionics version: 5670-WA; similar to 2C51 or 6385
  • 5671 – 25 kW, 10 MHz Forced-air cooled power triode, 11 V/285 A filament
  • 5672 – Subminiature power pentode, 1.25 V/50 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 5674 – Directly heated dual, compensating electrometer space charge grid tetrode for use in the 2 branches of a differential-in, differential-out bridge circuit, 3.8 V/90 mA filament, U6A base
  • 5675Pencil-type Glass/metal medium-μ triode, 6.3 V/135 mA heater
  • 5676 – Subminiature VHF triode, 1.25 V/120 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 5677 – Subminiature UHF triode, 1.25 V/60 mA filament, all-glass elliptical cross-section envelope with 4 inline wire-ends
  • 5678/DF60 – Subminiature, shielded RF pentode with a split suppressor grid, its halves tied to the positive resp. negative 1.25 V/50 mA filament end, all-glass elliptical cross-section envelope with 5 long inline wire-ends
  • 5679 – Dual diode, 6.3 V/150 mA heater, Loctal base
  • 5680 – 2.5 kW, 30 MHz Forced-air cooled power triode, 13 V/36 A filament
  • 5681 – 75 kW, 30 MHz Water-cooled power triode with coaxial terminals, 12 V/220 A filament
  • 5682 – 140 kW, 30 MHz Water-cooled power triode with coaxial terminals, 16.5 V/325 A filament
  • 5683 – 1.25 kV, 1 A Gas-filled triode thyratron, 2.5 V/6.3 A filament, UX4 Bayonet base
  • 5684 = EEV C3J/A = ELC3J/A – 1.25 kV, 2.5 A Xenon-filled triode thyratron with negative control characteristic, center-tapped 2.5 V/9 A filament, UX4 Bayonet base with anode on top cap
  • 5685 = EEV C6J/A = ELC6J/A – 1.25 kV, 6.4 A Xenon-filled triode thyratron with negative control characteristic, 2.5 V/21 A filament, B4D Superjumbo base with anode on top cap
  • 5686 – 8.25 W, 160 MHz Ruggedized beam power tetrode, 6.3 V/350 mA heater, Noval base
  • 5687 – Dual medium-μ triode with separate cathodes, center-tapped 12.6 V/450 mA resp. 6.3 V/900 mA heater, Noval base; avionics version: 5687-WA
  • 5690 – 1.12 kV, 2×375 mA Dual rectifier with separate cathodes and separate 6.3 V/1.2 A (each) heaters, Octal base
  • 5691Special Red ruggedized, long-life version of 6SL7-GT dual high-μ triode
  • 5692Special Red ruggedized, long-life version of 6SN7-GT dual medium-μ triode, extensively used in the SAGE computer systems
  • 5693Special Red ruggedized, long-life version of 6SJ7 sharp-cutoff pentode
  • 5694 – Pre-aged 6N7-G dual high-μ triode, Octal base
  • 5695 – 5 kV, 150 mA Mercury-vapor half-wave rectifier, 2.5 V/3 A filament, UX4 Bayonet base
  • 5696/EN92 (5663, 546) – 500 V, 25 mAavg, 100 mApeak, 2 Asurge Xenon-filled tetrode thyratron for industrial control systems, negative starter voltage, 6.3 V/150 mA heater, Miniature 7-pin base
  • 5697 – Subminiature triode, 625 mV/20 mA filament, all-glass elliptical cross-section envelope with 4 inline wire-ends
  • 5702 – Subminiature, dual-control pentode, 6.3 V/200 mA heater, all-glass round cross-section envelope but 7 long inline wire-ends; ruggedized versions: 5702-WA, 5702-WB = 6148
  • 5703 – Subminiature UHF triode, 6.3 V/200 mA heater, all-glass round cross-section envelope with 5 long wire-ends; ruggedized versions: 5703-WA, 5703-WB = 6149
  • 5704 – Subminiature diode, 6.3 V/150 mA heater, all-glass round cross-section envelope, but 4 long inline wire-ends; ruggedized version: 5704-WA
  • 5705 – 10 kW, 30 MHz Water-cooled power triode, 22 V/60 A filament
  • 5710 – 5 kW, 20 MHz Forced-air cooled power triode, 10 V/420 A filament
  • 5711 – Oil-cooled X-ray tube
  • 5712Superficial therapy tubehead with a 5711 inside
  • 5713 – 250 W, 220 MHz Forced-air cooled, coaxial power triode, half-indirect 3.3 V/11.5 A heater
  • 5718 – Subminiature medium-μ triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5719 – Subminiature low-microphonics, high-μ AF triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5721 – 125 mW, 2.5-12 GHz Reflex Klystron, 6.3 V/580 mA heater, 4-pin PeeWee base with external-cavity contact rings and top cap
  • 5722 – Directly heated, thermally-limited (=saturated) emission VHF noise diode, center-tapped 2-5.5 V/1.6 A uncoated Tungsten filament, Miniature 7-pin base
  • 5725/6187/6AS6-W, 7752 (Different pinout) – Avionics version of 6AS6 sharp-cutoff pentode
  • 5726 = 6097, 6AL5-W = E91AA/EAA901S – Ruggedized dual RF diode, Silicon-free 6.3 V/300 mA heater, Miniature 7-pin base
  • 5727/E91N = 2D21-W – Up to 750 g shock resistant 2D21
  • 5728 = FG-67 – 1 kV, 2.5 A Mercury-vapor triode thyratron, half-indirect 5 V/4.5 A heater, UX4 Bayonet base with anode on top cap
  • 5729Beam deflection, 30-channel analog multiplexer for telecomms transmitting channel banks, internal electrostatic focusing and deflection to determine through which one out of 30 grids the electron beam passes to the common anode, 6.3 V/450 mA heater, 42-pin base;[141] cf. 5738, 6090, 6091, 6170, 6324
  • 5730Cyclophon, a beam deflection, 30-channel analog demultiplexer for telecomms receiving channel banks, internal electrostatic focusing and deflection to determine which one out of 30 anodes receives the electron beam controlled by a common grid, 6.3 V/450 mA heater, 42-pin base
  • 5731 – Narrow-tolerance selected 955 Acorn triode used in Radiosonde weather balloon transmitters
  • 5732 – Ruggedized 6K7 pentode
  • 5734, 5734AMechanotron-type mechano-electronic displacement sensor - a vacuum triode with its anode mounted on a shaft that extends through a thin, flexible metal diaphragm, shaft movement is reflected in anode current, Fres = 12 kHz, 6.3 V/150 mA heater, metal envelope, circular 4-pin/wire-ends[142][143][101]
  • 5736 – 2.5 kW, 60 MHz Forced-air cooled power triode, 6 V/60 A filament
  • 5737 – 150 kW, 20 MHz Water-cooled power triode, 25 V/650 A filament
  • 5738Cyclophon, a beam deflection, secondary emission, 25-channel analog multiplexer, internal electrostatic focusing and deflection to determine which one out of 25 individually controllable dynodes receives the electron beam controlled by a common grid, 6.3 V/600 mA heater, 12-pin Diheptal (electron gun) plus JEDEC B26-53 26-pin (dynodes) bases;[144] cf. 5729, 6090, 6091, 6170, 6324
  • 5741 – 20 kV, 20 mA Radiation-cooled half-wave rectifier, 10 V/5 A filament, UX4 Bayonet base with anode on top cap
  • 5744 – Subminiature UHF triode, 6.3 V/200 mA heater, all-glass round cross-section envelope with 5 wire-ends; ruggedized version: 5744-WB = 6190, 6151
  • 5745, 5746, 5747, 5748 – X-ray tubes
  • 5749/6BA6-W – Ruggedized 6BA6/EF93 remote-cutoff RF pentode
  • 5750 – Ruggedized 6BE6/EK90 heptode pentagrid converter, shock resistant up to 450 g
  • 5751 – Dual low-noise, high-μ triode with separate cathodes, center-tapped 12.6 V/175 mA resp. 6.3 V/350 mA heater, Noval base; avionics version: 5751-WA
  • 5755 – Ruggedized, low microphonics, low-drift, separate cathodes dual triode used as precision DC amplifier in stabilized DC power supplies and analog computers, center-tapped 12.6 V/180 mA resp. 6.3 V/360 mA heater, Noval base
  • 5759 – 1 kW, 150 MHz Forced-air cooled power triode, center-tapped 7.5 V/24 A filament
  • 5760 (Water-cooled), 5761 (Forced-air cooled) – 1.5 kW, 150 MHz power triode, center-tapped 7.5 V/24 A filament
  • 5762/7C24 = RCA 4654, 5762A – 4 kW, 30 MHz Forced-air cooled power triode, center-tapped 12.6 V/29 A filament
  • 5763 (6.0 V/750 mA heater), 6417 (12.6 V/375 mA heater) – 12 W, 175 MHz Beam power tetrode, Noval base
  • 5764 – 3.3 GHz Rocket-type disk-seal planar UHF triode, 6.3 V/425 mA heater; supersedes 2C37
  • 5765 – 2.9 GHz Rocket-type disk-seal planar UHF triode, 6.3 V/400 mA heater
  • 5766 – 2C37 Rocket-type disk-seal planar UHF triode with folded anode disk
  • 5767, 6481 (Lower anode-to-cathode capacitance) – 3.3 GHz Rocket-type disk-seal planar UHF triode; 2C37 with folded discs, 6.3 V/400 mA heater
  • 5768 – 3 GHz Rocket-type disk-seal planar high-μ triode, 6.3 V/400 mA heater
  • 5769 – 3" Image Orthicon, 6.3 V/600 mA heater
  • 5770 – 50 kW, 20 MHz Water+forced-air cooled power triode, 11 V/285 A heater
  • 5771 – 22.5 kW, 25 MHz Water+forced-air cooled power triode, 7.5 V/170 A heater
  • 5779 – Educational Ignitron with a glass envelope
  • 5780 – 250 kW, 8.5-9.6 GHz Pulsed Magnetron, 20 V/4 A heater
  • 5781, 5782 – X-ray tubes
  • 5783 – Subminiature 86 V voltage-regulator tube, all-glass elliptical cross-section envelope with 3 long inline wire-ends; ruggedized versions: 5783-WA, 5783-WB
  • 5784 – Subminiature, dual-control VHF pentode, 6.3 V/200 mA heater, all-glass round cross-section envelope but 7 long wire-ends; ruggedized versions: 5784-WA, 5784-WB
  • 5785 – Subminiature diode, 1.25 V/15 mA filament, all-glass elliptical cross-section envelope with 3 inline wire-ends
  • 5786 – 600 W, 160 MHz Forced-air cooled power triode, center-tapped 11 V/12.5 A filament
  • 5787 – Subminiature 98 V voltage-regulator tube, all-glass round cross-section envelope with 3 long wire-ends; ruggedized version: 5787-WA
  • 5788 – Ignitron similar to 5555
  • 5789 – 40 kW, 34.512-35.208 GHz Pulsed Magnetron, 6 V/2 A heater
  • 5790, 5791, 5792, 5793 – ATR cells
  • 5794, 5794A/6562 – 600 mW, 1.68 GHz Pencil-type power triode fixed-tuned oscillator assembly with integral cathode and anode cavity resonators used in Radiosonde weather balloon transmitters, 5.2-6.6 V/160 mA heater
  • 5795 – 1 MW, 3.1-3.5 GHz Forced-air cooled, pulsed Magnetron, 107 V/3.65 A heater
  • 5797 – Ruggedized, subminiature low (26.5-50 V) anode voltage, semiremote-cutoff pentode, 26.5 V/45 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5798 – Subminiature dual low (26.5-50 V) anode voltage, medium-μ triode, 26.5 V/90 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5799 – 3 kV, 200 µA Subminiature half-wave rectifier, 1.25 V/10 mA filament
  • 5800, 5803 – Subminiature electrometer tetrodes, 1.25 V/10 mA filament
  • 5801 (High-μ), 5802 (low-μ) – Subminiature triodes, 1.25 V/10 mA filament
  • 5812 – 10 W, 165 MHz Beam power pentode, center-tapped 6 V/650 mA oxide-coated quickstart filament, Miniature 7-pin base
  • 5813 – 1.8" Slow scan video camera tube, 6.3 V/600 mA heater
  • 5814, 5814A – Ruggedized, industrial/computer-rated version of 12AU7/ECC82 dual medium-μ triode with a Silicon-free, center-tapped 12.6 V/175 mA resp. 6.3 V/350 mA heater; avionics versions: 5814-WA, 5814-WB
  • 5817 (4.8-5 GHz), 5818 (5-5.2 GHz) – 1.6 W Forced-air cooled Reflex Klystrons used in microwave radio relais, 6.3 V/1.5 A heater
  • 5819 – 10-Stage, head-on S9 photomultiplier, Diheptal 14-pin base
  • 5820, 5820A, 5820A/L (Longer-life, non-deteriorating glass target) – 1.8" Image Orthicon, 6.3 V/600 mA heater, Diheptal 14-pin base
  • 5821 – 1.2 kV, 9 A Water-cooled Ignitron
  • 5822, 5822A – 1.2 kV, 20 A Water-cooled Ignitron
  • 5823/Z900T – 200 V, 25 mAavg, 100 mApeak Gas-filled, cold-cathode AC trigger triode, Miniature 7-pin base
  • 5824 – Premium version of 25B6-G power pentode
  • 5825 – 60 kV, 2 mA Half-wave rectifier, 1.6 V/1.25 A heater, UX4 base with anode on top cap
  • 5826 – 1.6" Image Orthicon, magnetic focus and deflection, 6.3 V/600 mA heater, Diheptal 14-pin base
  • 5828 – Subminiature medium-μ triode, 1.25 V/10 mA filament
  • 5829-WA – Ruggedized, subminiature avionics separate cathodes dual diode, 6.3 V/150 mA heater, all-glass round cross-section envelope with 7 long wire-ends
  • 5831 – 150 kW Water-cooled beam power tetrode, 6 V/2.22 kA heater
  • 5833 – 35 kW, 6 MHz Forced-air cooled power triode, 3-phase filaments internally star-connected with center/neutral available, 20 V/143 AY each
  • 5834 = 649 (2.5 V/7 A filament, 2 A anode), 5835 = 653 (2.5 V/9.5 A filament, 3 A anode) – 900 V Half-wave Mercury-vapor rectifiers, UX4 Bayonet base
  • 5836
    Raytheon RK5836
    – 250 mW, 1.6-6.5 GHz Reflex Klystron, 6.3 V/750 mA heater, 4-pin PeeWee base with external-cavity contact rings and top cap; pulse-rated variant of type 6BL6
  • 5837 – 150 mW, 0.55-3.8 GHz Reflex Klystron, 6.3 V/675 mA heater, 4-pin PeeWee base with external-cavity contact rings and top cap; pulse-rated variant of type 6BM6
  • 5838 (12.6 V/600 mA heater), 5839 (26.5 V/255 mA heater), 5852 (6.3 V/1.2 A heater) – Ruggedized, pre-aged 6X5/EZ35 full-wave rectifier
  • 5840 (Suppressor grid internally tied to cathode), 6205 (dual-control) – Subminiature sharp-cutoff RF pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5841 – 900 V Subminiature Corona voltage-regulator tube
  • 5842 = Western Electric 417A = CSF F7004 – Medium-μ triode used in grounded-grid amplifiers, 6.3 V/300 mA heater, Noval base (not to be confused with the 7004=TBL2/300 RF power triode)
  • 5844 – Dual medium-μ triode, 6.3 V/300 mA heater, Miniature 7-pin base
  • 5845 – Directly heated, dual 300 V, 1 mA thermally-limited (=saturated) emission diode used as a heating current-controlled, variable series resistor in voltage/current stabilizer circuits, or as an RMS heating current-to-DC anode current converter, or as a noise diode, center-tapped 5 V/435 mAmax uncoated Tungsten filament, Miniature 7-pin base; cf. Tesla RA0007, YA1000
  • 5846 – 9.28 GHz Reference microwave cavity
  • 5847 = Western Electric 404A, 5847A – Frame-grid sharp-cutoff pentode, 6.3 V/300 mA heater, Noval base
  • 5851 – Ruggedized, subminiature 400 MHz beam power pentode, center-tapped 2.5 V/55 mA resp. 1.25 V/110 mA filament, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5852 – See 5838
  • 5853 – TR cell
  • 5854 – 0.8" Image Iconoscope, 6.3 V/630 mA heater
  • 5857Secondary emission VHF hexode, 6.3 V/450 mA heater, Noval base
  • 5859, 5860 – X-ray tubes
  • 5861/EC55 = LaRadiotechnique R243 – 10 W, 3 GHz Rocket-type disk-seal power triode, 6.3 V/400 mA heater
  • 5864 – ATR cell
  • 5865 – TR cell
  • 5866 = TB2.5/300 (6.3 V/5.4 A filament, 135 W anode), 5866A = 7986 = TB2.5/400 (6.3 V/5.8 A filament, 150 W) – 150 MHz Radiation-cooled power triode
  • 5867 = TB3/750, 5867A – 350 W, 100 MHz Radiation-cooled power triode, 5 V/14.1 A filament
  • 5868 = TB4/1250 – 450 W, 100 MHz Radiation-cooled power triode, 10 V/9.9 A filament
  • 5869 – 13 kV, 1 A Mercury-vapor triode thyratron with negative control characteristic, 5 V/6.5 A filament, 4-pin base with anode on top cap
  • 5870 – 27 kV, 2.5 A Mercury-vapor triode thyratron with negative control characteristic, 5 V/14 A filament, 3-pin base with anode on top cap
  • 5871 – Ruggedized 6V6-GT beam power tetrode
  • 5873 – Subminiature dual medium-μ triode, 6.3 V/300 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5875 – Subminiature sharp-cutoff pentode used in Radiosonde weather balloon transmitters, 1.25 V/100 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 5876, 5876A – 6.25 W, 1.7 GHz Ruggedized, Pencil-type, glass/metal, disk-seal, high-μ UHF power triode, 6.3 V/135 mA heater
  • 5877 (2.5 V/10.8 A filament, 3.2 A anode), 5878 (2.5 V/21 A filament, 6.4 A) – 1.5 kV Gas-filled triode thyratrons with negative control characteristic, 4-pin base with anode on top cap
  • 5879 – Low microphony, low-noise, low-hum, sharp-cutoff AF pentode, 6.3 V/150 mA heater, Noval base
  • 5881 – Ruggedized 6L6 AF beam power tetrode with 20% higher anode and screen grid dissipation
  • 5883 – ATR cell
  • 5884, 5885 – Subminiature dual electrometer tetrodes, 1.25 V/10 mA filament, all-glass wire-ended
  • 5886 – Subminiature electrometer pentode, 1.25 V/10 mA filament, all-glass wire-ended
  • 5887, 5888 (3-pin PeeWee base) – γ-detecting, Halogen-quenched, Neon Geiger-Müller tubes, stainless steel envelope
  • 5889 – Subminiature electrometer pentode, 12 V anode voltage, 1.25 V/7.5 mA filament, 4+1-pin/wire-ends
  • 5890 – 10 kV, 10 W Remote-cutoff beam power pentode used as 500 µA shunt regulator, 6.3 V/600 mA heater, 7-pin Duodecal base with anode on top cap
  • 5891 – 25 kW, 10 MHz Forced-air cooled power triode, 3-phase filaments internally star-connected with center/neutral available, 11 V/95 AY each
  • 5892 = EL6B – 920 V, 6.4 A Xenon-filled, half-wave rectifier with a Tantalum anode on top cap, 2.5 V/21 A filament, 4-pin base
  • 5893Pencil-type, glass/metal, medium-μ triode, 6.0 V/280 mA heater
  • 5894, 5894B = 8738 – 2×20 W, 250 MHz Dual beam power tetrode, center-tapped 12.6 V/900 mA resp. 6.3 V/1.8 A heater, Septar base with anodes on top pins
  • 5895 – 2×8 W, 186 MHz Dual RF power tetrode, 6.3 V/680 mA heater, Loctal base
  • 5896 (6.3 V/300 mA heater), 5903 (26.5 V/75 mA heater) – Subminiature separate cathodes dual diode, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5897 – Ruggedized, subminiature medium-μ UHF triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5898 – Ruggedized, subminiature high-μ triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5899 – Ruggedized, subminiature, wideband, semiremote-cutoff pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5900 – Ruggedized, subminiature semiremote-cutoff pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5901 – Ruggedized, subminiature semiremote-cutoff UHF pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5902/EL71 – Ruggedized, subminiature AF beam power pentode, 6.3 V/450 mA heater, all-glass round cross-section envelope with 8 long circular wire-ends; avionics version: 5902-WA
  • 5903 – See 5896
  • 5904 – Ruggedized, subminiature low (26.5-55 V) anode voltage medium-μ triode, 26.5 V/45 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5905 – Ruggedized, subminiature low (26.5-55 V) anode voltage sharp-cutoff UHF pentode, 26.5 V/45 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 59065840 Subminiature pentode with a 26.5 V/45 mA heater
  • 5907 – Ruggedized, subminiature, low (26.5-55 V) anode voltage, remote-cutoff RF pentode, 26.5 V/45 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5908 – Ruggedized, subminiature, low (26.5-55 V) anode voltage, dual-control, sharp-cutoff VHF pentode used as a gated or gain-controlled amplifier, designed for both heater and anode to run directly off the standard avionics 28-volts DC bus, 26.5 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends base; similar to 5784
  • 5910 – Sharp-cutoff pentode used in Radiosonde weather balloon transmitters, 1.4 V/50 mA filament, Miniature 7-pin base
  • 5913/6007/DL67 – Subminiature power pentode, 1.25 V/13.3 mA filament, all-glass round cross-section envelope, inline 5-pin/wire-ends
  • 5915/EH960/EH900S, 5915A – Sharp-cutoff switching heptode used in high speed digital computer equipment, Silicon-free 6.3 V/300 mA heater, Miniature 7-pin base
  • 5916 – 5636 Ruggedized, subminiature pentode with a 26.5 V/45 mA heater
  • 5917 – 5 kW, 110 MHz Water-cooled power triode, 7.5 V/48 A filament
  • 5920/E90CC – Common cathode dual triode used as a flip-flop in computers, Silicon-free 6.3 V/400 mA heater, Miniature 7-pin base
  • 5921, 5922 – ATR cells
  • 5923 = TBW6/6000 – 6 kW, 75 MHz Water-cooled power triode, center-tapped 12.6 V/33 A filament
  • 5924, 5924A – 5 kW, 75 MHz Forced-air cooled power triode, center-tapped 12.6 V/33 A filament
  • 5927 – TR cell
  • 5929 – 4.4-5 GHz Power Traveling-wave tube, 6.3 V/2 A heater
  • 5930 – 15 W Ruggedized AF power triode, 2.5 V/2.5 A filament, 4-pin base
  • 5931/5U4-WG – Ruggedized full-wave rectifier, 5 V/3 A heater, 5-pin Octal base
  • 5932/6L6-WGA – Ruggedized beam power tetrode, 6.3 V/900 mA heater, 7-pin Octal base
  • 5933/807-W – Ruggedized beam power tetrode, 6.3 V/900 mA heater, 5-pin Octal base
  • 5934 – 20 kV, 25 mA Half-wave rectifier, 2.5 V/6 A filament, 4-pin base with anode on top cap
  • 5935 – Subminiature diode used in VHF voltmeters, 6.3 V/150 mA heater, all-glass wire-ended
  • 5936 – 70 kW, 15 MHz Water-cooled power triode, 20 V/143 A filament
  • 5939 – TR cell
  • 5942, 5944 – β and γ-detecting, Halogen-quenched Neon Geiger-Müller tube, stainless steel envelope
  • 5946 – 250 W, 1.3 GHz Forced air cooled, anode-pulsed, coaxial power triode, half-indirect 6.3 V/3.4 A heater
  • 5947 – Directly heated, thermally-limited (=saturated) emission diode, 4.44 V/1.75 A uncoated Tungsten filament, Octal base
  • 5948 = Toshiba 4G48P, 5948A – Hydrogen triode thyratron, 6.3 V/29 A heater
  • 5949 = Toshiba 3G49P, 5949A – Hydrogen triode thyratron, 6.3 V/18.5 A heater
  • 5950 – 700 V Subminiature Corona voltage-regulator tube
  • 5956, 5957, 5958, 5959 – Pulse-rated Hydrogen triode thyratrons
  • 5960 – 1.3 kV, 90 mAavg, 100 Apeak Avionics arc-discharge triode, 4-pin base
  • 5961 – Ruggedized 6SA7 heptode pentagrid converter
  • 5962 – 700 V/2...55 µA Corona voltage-regulator tube, Miniature 7-pin base with anode on top cap
  • 5963 (Noval base), 5964 (Miniature 7-pin base, common cathode), 5965 (Noval base) – Industrial/computer-rated versions of 12AV7 dual medium-μ triode with a high zero-bias anode current and a Silicon-free, center-tapped (except 5964) 12.6 V/225 mA resp. 6.3 V/450 mA heater
  • 5966, 6794Bayard–Alpert vacuum gauge
  • 5967, 5968 – Subminiature dual VHF triodes, 1.25 V/120 mA filament, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5969 – Subminiature dual VHF tetrode, 1.25 V/200 mA filament, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5970 – Subminiature dual VHF pentode, 1.25 V/160 mA filament, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5971 – Ruggedized, subminiature VHF triode, 1.25 V/80 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 5972 – Subminiature, remote-cutoff pentode, 1.25 V/60 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 5973, 5973A – 75 kV, 1 A Half-wave rectifier, 16 V/19.1 A filament
  • 5974 – 125 kV, 300 mA Oil-cooled, half-wave rectifier, 10 V/50 A filament
  • 5975 – Subminiature triode, 6.3 V/175 mA heater, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 5976 – 90 mW, 6.25-7.425 GHz Reflex Klystron, 6.3 V/440 mA heater
  • 5977 – Ruggedized, subminiature medium-μ triode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5978 – γ-detecting, high-pressure, ceramic/metal ionization chamber with a guard ring
  • 5980 – Cartridge-type, self-quenched Geiger-Müller tube
  • 5981 – See 5649
  • 5986 – 70 kW, 15 MHz Water-cooled power triode, 12 V/300 A filament
  • 5987 – Ruggedized, subminiature low-μ power triode, 6.3 V/450 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 5992 – Ruggedized, pre-aged 6V6 beam power tetrode with a 6.3 V/600 mA heater
  • 5993 – Ruggedized, pre-aged 6X4/6BX4/EZ90 full-wave rectifier with a 6.3 V/800 mA heater and a Noval base
  • 5995 – 850 V, 45 mA Subminiature half-wave rectifier, 6.3 V/300 mA heater
  • 5997Reliatron Image converter for X-ray diagnostics
  • 5998, 5998A – 2×15 W Dual power triode used as series-pass regulator in stabilized DC power supplies, 6.3 V/2.4 A heater, Octal base

LoVTList of American EIA professional tubes

6000s

  • 6000 – 25 W, 100 MHz Beam power tetrode, 26.5 V/280 mA heater, Octal base
  • 6004 – 1.4 kV, 2×375 mA Full-wave rectifier, 5.0 V/2.0 A heater, 5-pin Octal base with dual anode caps
  • 6005/6AQ5-W – Ruggedized 6AQ5/EL90 AF Beam power tetrode
  • 6006 – Ruggedized 6SG7 semiremote-cutoff pentode
  • 6007/DL67 – See 5913/6007/DL67
  • 6008/DF67 – Subminiature AF pentode used in hearing aids, 625 mV/13.3 mA filament, all-glass round cross-section envelope, inline 5-pin/wire-ends base
  • 6011 = 710 – 1.5 kV, 2.5 A Gas/Mercury-vapor thyratron, 2.5 V/9 A filament, 4-pin base with anode on top cap
  • 6012 – 1.3 kV, 500 mA Gas-filled tetrode thyratron, negative control characteristic, 6.3 V/2.6 A heater, 6-pin Octal base
  • 6013 = EL3B (UX4 Bayonet base w/filament center-tap), 6015 = EL6F (2 cables) – 920 V, 2.5 A Xenon-filled, half-wave rectifiers, Tantalum anode on top cap, 2.5 V/9 A filament
  • 6014 = EEV C1K = ELC1K – 1.25 kV, 1 A Xenon-filled triode thyratron, negative control characteristic, 2.5 V/6.3 A heater, UX4 Bayonet base
  • 6017 – 1 kW, 400 MHz Forced-air cooled, ceramic/metal, coaxial VHF power triode used in grounded-grid amplifiers, half-indirect 10 V/17 A heater
  • 6018Rocket-type UHF Pulse power triode, 6.3 V/400 mA heater
  • 6019 – 2 kW, 900 MHz Water jacket-cooled, ceramic/metal UHF power tetrode used in grounded-grid amplifiers, half-indirect 6.3 V/24 A heater
  • 6021/ECC70, 6021-WA – Ruggedized, subminiature, separate cathodes dual medium-μ UHF triode, 6.3 V/300 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends base
  • 6024, 6033, 6034 – ATR cells
  • 6026 – Subminiature RF triode used in Radiosonde weather balloon transmitters, 5.2-6.6 V/200 mA heater, all-glass round cross-section envelope, circular 5-pin/wire-ends
  • 6027, 6027H = YJ1060 – Pulsed Magnetron; 2J42 with an additional magnet
  • 6028 = Western Electric 408A5654/6096/6AK5-W/E95F 400 MHz Pentode with a 20 V/50 mA heater
  • 6029 – Subminiature triode, 1.25 V/200 mA filament, all-glass elliptical cross-section envelope with 4 inline wire-ends
  • 6032, 6032A – S1→P20 Image converter (S1 infrared (800 nm) photocathode, P20 yellow-green Phosphor)
  • 6035, 6038 – TR cells
  • 6039 – 7 kW, 220 MHz Water-cooled, ceramic/metal, coaxial VHF power triode used in grounded-grid amplifiers, 5 V/78 A filament; 9C24 with a thoriated Tungsten filament consuming 74.2% less power
  • 6040 (9.308 GHz), 6041 (9.312 GHz) – Reference microwave cavities
  • 6042 (25 V/150 mA heater), 6180 (6.3 V/600 mA heater) – Ruggedized 6SN7-GT dual triodes
  • 6043 = Raytheon QK159 – 2.95-3.275 GHz Reflex Klystron, 6.3 V/650 mA heater, Octal base
  • 6044 – 500 V, 6.4 A Gas-filled triode thyratron, negative control characteristic, 2.5 V/17 A filament
  • 6045 – Ruggedized, dual low-μ triode, 6.3 V/350 mA heater, Miniature 7-pin base
  • 6046 – 25L6-GT Beam power tetrode with a Silicon-free heater and a low-secondary emission control grid
  • 6047Additron, a triple-control grid, split-anode tetrode for use as a single-bit digital full adder, 6.3 V/150 mA heater, Noval base[145] (technically a hexode)
  • 6049 – Ruggedized, subminiature remote-cutoff UHF pentode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends base
  • 6050 – Subminiature triode, 1.25 V/120 mA filament, all-glass elliptical cross-section envelope with 4 inline wire-ends
  • 6051 – Subminiature power pentode, 1.25 V/100 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 6052 (6.3 V/300 mA heater), 6053 (26.5 V/75 mA heater) – Ruggedized, subminiature dual UHF diode, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6055 – Ruggedized, subminiature, low (26.5-55 V) anode voltage, medium-μ UHF triode, 26.5 V/45 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6056 – Ruggedized, subminiature, low (26.5-55 V) anode voltage, remote-cutoff UHF pentode, 26.5 V/45 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6057/ECC803S – Ruggedized, long-life (>10000h) 12AX7/ECC83 dual high-μ triode with a Silicon-free heater
  • 6058 – Ruggedized 6AL5/EAA91 dual diode
  • 6059 – Ruggedized 6BR7, 6J7 low-microphonics pentode
  • 6060, M8162 – Ruggedized 12AT7/ECC81 dual high-μ triode
  • 6061 – Ruggedized 6V6-GT beam power tetrode with a Noval base
  • 6062 – 12 W, 175 MHz VHF beam power tetrode, 6 V/750 mA heater, Noval base
  • 6063/6X4-WA/E90Z – Ruggedized 6X4/6BX4/EZ90 full-wave rectifier
  • 6064, M8083 – Ruggedized 6AM6/EF91 sharp-cutoff RF pentode
  • 6065 – Ruggedized 6CQ6/EF92 remote-cutoff RF pentode
  • 6066 – Ruggedized 6AT6/EBC90 dual diode + triode
  • 6067, 6189/E82CC, 6189A, M8136 – Ruggedized 12AU7/ECC82 dual medium-μ triode
  • 6069 = 6AK5/EF95
  • 6072 – Ruggedized 12AY7 dual medium-μ triode, shock resistant up to 600 g
  • 6073/0A2-WA – 150 V Voltage-regulator tube, Miniature 7-pin base
  • 6074/6627/0B2-WA – 108 V Voltage-regulator tube, Miniature 7-pin base
  • 6075 = QBW5/3500 (Water-cooled), 6076 = QBL5/3500 (forced-air cooled) – 3 kW, 110 MHz power tetrodes, 6.3 V/32.5 A filament
  • 6077 = TBW12/100 (Water-cooled, 100 kW), 6078 = TBL12/100 (forced-air cooled, 45 kW) – 15 MHz power triodes, 17.5 V/196 A filament
  • 6080 (6.3 V/2.5 A heater), 6082, 6082A (26.5 V/600 mA heater) – Ruggedized 6AS7-G/ECC230 very-low impedance dual power triode, now popular as output transformerless audio amplifiers in audiophile gear, shock resistant up to 450 g; avionics versions: 6080-WA, 6080-WB, 6080S
  • 6081 – ATR cell
  • 6083 = PE1/100 = YL1200 – 45 W, 60 MHz Radiation-cooled power pentode, 12.6 V/1.35 A heater, Septar base
  • 6084/E80F – Ruggedized RF/IF/AF pentode, 6.3 V/300 mA heater, Noval base
  • 6085/E80CC – Ruggedized, separate cathodes dual triode used as DC or AF amplifier, center-tapped 6.3 V/600 mA resp. 12.6 V/300 mA heater, Noval base
  • 6086 = Philips 18042 – Pentode used in telephone equipment, 18 V/100 mA heater, Noval base
  • 6087 (Half-indirect 2 A heater), 6106 (half-indirect 1.7 A heater), 6853 = Bendix TE-45 (pre-aged, hard glass, half-indirect 5 V/1.7 A heater) – Ruggedized 5Y3-GB full-wave rectifier
  • 6088 – Subminiature pentode, 1.25 V/20 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 6089 – 9.28 GHz Reference microwave cavity
  • 6090Cyclophon, a beam deflection, 18-channel analog demultiplexer for telecomms receiving channel banks, internal electrostatic focusing and deflection to determine which one out of 18 anodes receives the electron beam controlled by a common grid, 6.3 V/670 mA heater, 30-pin base;[146] cf. 5729, 5738, 6091, 6170, 6324
  • 6091 – Beam deflection, 25-channel analog multiplexer for telecomms transmitting channel banks, internal electrostatic focusing and deflection to determine through which one out of 25 grids the electron beam passes to the common anode, 6.3 V/670 mA heater, 30-pin base;[147] cf. 5729, 5738, 6090, 6170, 6324
  • 6092 – Subminiature power pentode, 1.25 V/50 mA filament, all-glass elliptical cross-section envelope with 5 inline wire-ends
  • 6094 – 12,5 W Ruggedized, hard glass 6005/6AQ5-W beam power tetrode with a 6.3 V/600 mA heater and a Noval base with Gold-plated pins
  • 6095 – Renamed to 6AQ5/EL90
  • 6096 – See 5654/6096/6AK5-W/E95F
  • 6097 – See 5726
  • 6098/6AR6-WA, 6384 (Hard glass envelope) – Ruggedized 6AR6 beam power tetrode with a 21 W anode
  • 6100/6C4-WA – Ruggedized 6C4/EC90 medium-μ triode
  • 6101 – Ruggedized dual medium-μ triode, 6.3 V/450 mA heater, Miniature 7-pin base
  • 6102 – 40 kV, 150 mA Oil-cooled half-wave rectifier, 5 V/7.2 A heater
  • 6103 – 20 kV, 150 mA Forced-air cooled half-wave rectifier, 5 V/7.2 A heater
  • 6106 – See 6087
  • 6110 – Ruggedized, subminiature, separate cathodes dual diode, 6.3 V/150 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends
  • 6111 (Medium-μ), 6112 (high-μ), 6113 – Subminiature, separate cathodes dual UHF triode, 6.3 V/300 mA heater, all-glass round cross-section envelope, circular 8-pin/wire-ends base; ruggedized versions: 6111-WA, 6112-WA
  • 6115, 6584 (Reduced repeller voltage variation with frequency) – 5.1-5.9 GHz Reflex Klystron, 6.3 V heater, Octal base
  • 6116 = Bendix TK62 – 30 mW, 8.5 to 9.66 GHz Reflex Klystron, 6.3 V/465-880 mA heater, Octal base; 2K45 with diode thermal tuning
  • 6117 – TR cell
  • 6118 – Ruggedized 6Q7 dual diode + triode
  • 6119 – 2 kV Subminiature Corona voltage-regulator tube
  • 6121 – 10h lifespan, subminiature VHF triode, 1.25 V/120 mA filament, all-glass elliptical cross-section envelope with 4 inline wire-ends
  • 6130/3C45 – 3 kV, 45 mAavg, 1.5 ARMS, 35 Apeak Hydrogen triode thyratron, positive control characteristic, half-indirect 6.3 V/2-2.5 A heater, Micanol UX4 base with anode on top cap
  • 6132 – Ruggedized 6CH6/EL821 power pentode
  • 6133 – 1.2-3.75 GHz Reflex Klystron, 6.3 V/650 mA heater, Octal base
  • 6134 – Ruggedized 6AC7 sharp-cutoff pentode
  • 6135 – Ruggedized 6C4/EC90 VHF triode with a 6.3 V/175 mA heater
  • 6136 – Ruggedized 6AU6/EF94 sharp-cutoff pentode
  • 6137 – Ruggedized 6SK7 remote-cutoff pentode
  • 6140 – 100 V, 4 to 8 mA Voltage-regulator tube, Noval base
  • 6141 = Western Electric 427A – 100 V, 5 to 40 mA Voltage-regulator tube with a keep-alive (primer) electrode, Noval base
  • 6142 – 150 V, 75 to 400 µA Voltage-regulator tube with 2 axial leads like a resistor
  • 6143 – 1.2 kV, 100 µA Subminiature Corona voltage-regulator tube
  • 6144 = Bendix TT-1 – Directly heated, thermally-limited (=saturated) emission coaxial UHF noise diode with 50Ω nominal output impedance, 3.2 V/2.5 A filament
  • 6145 – Sharp-cu