Note: Typecode explained
above. See also
RETMA tube designation ==="0 volt" gas-filled
cold cathode tubes=== First character is numeric zero, not letter O. ====
Voltage stabilisers and references==== Function in a similar way to a
Zener diode, at higher voltages. Letter order (A-B-C) indicates increasing voltage ratings on octal-based regulators and decreasing voltage ratings on miniature-based regulators. •
0A2 – 150 volt regulator, 7-pin miniature base •
0A3 – 75 volt regulator, octal base, aka
VR75 •
0B2 – 105 volt regulator, 7-pin miniature base •
0B3 – 90 volt regulator, octal base, aka
VR90 •
0C2 – 75 volt regulator, 7-pin miniature base •
0C3 – 105 volt regulator, octal base, aka
VR105 •
0D3 – 150 volt regulator, octal base, aka
VR150 Other cold-cathode tubes •
0A4G – 25 mAavg, 100mApeak Gas triode 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 •
0Y4 – 40 ≤ I ≤ 75 mA Half-wave gas rectifier with a starter anode, 5-pin octal base •
0Z4 – 30 ≤ I ≤ 90 mA Argon-filled, full-wave gas rectifier, octal base. Widely used in
vibrator power supplies in early automobile radio receivers.
1 volt heater/filament tubes 1.25 volt DC filament subminiature tubes The following tubes were used in post-World War II
walkie-talkies and pocket-sized portable radios. All have 1.25 volt DC filaments and directly heated cathodes. Some specify which end of the filament is to be powered by the positive side of the filament power supply (usually a battery). All have glass bodies that measure from wide, and from in overall length. •
1C8 –
Pentagrid converter,
R8 •
1D3 –
Low-mu high-frequency triode,
R8 •
1E8 – Pentagrid converter,
R8 •
1Q6 – Diode, pentode,
R8 •
1S6 – Diode, pentode,
R8 •
1T6 – Diode, pentode,
R8 •
1V5 – Power pentode,
R8 •
1V6 – Triode-pentode converter,
FL •
1W5 – Sharp-cutoff pentode,
R8 •
1AC5 – Power pentode,
FL •
1AD4 – Sharp-
cutoff pentode,
FL •
1AD5 – Sharp-cutoff pentode,
R8 •
1AE5 – Heptode mixer,
FL •
1AG4 – Power pentode,
FL •
1AG5 – Diode, pentode,
FL •
1AH4 – RF pentode,
FL •
1AJ5 – Diode, sharp-cutoff pentode,
FL •
1AK4 – Sharp-cutoff pentode,
FL •
1AK5 – Diode, sharp-cutoff pentode,
FL 1.4 volt DC filament tubes •
1A3 – High frequency diode with indirectly heated cathode. Used as a detector in some portable AM/FM receivers. •
1A7GT/DK32 –
Pentagrid converter, re-engineered version of types
1A6 and
1D7-G, designed for use in portable AC/DC/Dry-cell battery radios introduced in 1938. Has 1.4 V/50 mA filament. •
1B7-GT – Re-engineered version of types
1C6 and
1C7-G, designed for use in dry-cell battery radios with shortwave bands. Has 1.4 V/100 mA filament •
1G6-G – Dual power triode. "GT" version also available. •
1L6 – Pentagrid frequency changer for battery radios with 50 mA filament •
1LA6 (Loctal) and later
1L6 (7-pin miniature) – Battery pentagrid converter for Zenith Trans-Oceanic
shortwave radio, 50 mA filament •
1LB6 – Superheterodyne mixer for battery-operated radios •
1LC6 – Similar to type
1LA6, but with higher conversion
transconductance •
1R5/DK91 –
Pentagrid converter, anode voltage in the 45...90 volt range. •
1S4 – Power output pentode
Class-A amplifier, anode voltage in the 45...90 volt range. •
1S5 – Sharp-
cutoff pentode Class-A amplifier, and diode, used as detector and first A.F. stage in battery radio receivers. Anode voltage in the 67...90 volt range. •
1T4/DF91 – Remote-cutoff R.F. Pentode Class-A amplifier, Miniature 7-pin base, used as R.F. and I.F. amplifier in battery radio receivers. •
1U4 – Sharp-cutoff R.F. Pentode Class-A amplifier, Miniature 7-pin base, used as R.F. and I.F. amplifier in battery radio receivers, similar characteristics to 6BA6. •
1U6 – Nearly identical to type
1L6, but with a 1.4 V/25 mA filament
"1" prefix for home receivers These tubes were made for
home storage battery receivers manufactured during the early to mid-1930s; all have 2.0 volt DC filaments despite the 1-prefix, intended to distinguish them from the 2.5 volt AC heated tubes listed below •
1A4-p – Remote-cutoff pentode •
1A4-t – Remote-cutoff tetrode •
1A6 –
Pentagrid converter up to only 10 MHz due to low heater power (2 V/60 mA) and consequent low emission in the oscillator section; also occasionally used as a grid-leak detector •
1B4-p – Sharp-cutoff pentode •
1B4-t – Sharp-cutoff tetrode •
1B5 – Dual detector diode,
medium-mu triode. Usually numbered
1B5/25S •
1C5 – Power pentode (similar to 3Q5 except for filament) •
1C6 – Pentagrid converter;
1A6, with double the heater power and double the frequency range •
1C7-G – Octal version of type
1C6. •
1D5-Gp – Octal version of type
1A4-p. •
1D5-Gt – Octal version of type
1A4-t. (
Note: This is a shouldered "G" octal, not a cylindrical "GT" octal.) •
1D7-G – Octal version of type
1A6. •
1E5-Gp – Octal version of type
1B4-p. •
1E5-Gt – Octal version of type
1B4-t. (
Note: This is a shouldered "G" octal, not a cylindrical "GT" octal.) •
1E7-G – Dual power pentode for use as a driver when parallel-connected, or as a push-pull output. "GT" version also available •
1F4 – Power pentode •
1F5-G – Octal version of
1F4. •
1F6 – Duplex diode, sharp-cutoff pentode •
1F7-G – Octal version of type
1F6 •
1G4-GT/G – Octal triode, mu 8.8 •
1G5-G – Power pentode •
1H4-G – Medium-mu triode, can be used as a power triode. Octal version of type
30, which is an upgraded version of type
01-A. "GT" version also available. •
1H6-G – Octal version of type
1B5/25S. "GT" version also available. •
1J5-G (950) – AF Power pentode •
1J6-G – Dual power triode, octal version of type
19. "GT" version also available.
CRT anode rectifiers •
1G3GT – Octal High-voltage rectifier. Same Characteristics as 1B3GT. Many listed and labeled as 1B3GT/1G3GT. •
1H2 – Noval High-voltage rectifier with 1.4 V/550 mA filament •
1J3GT – Octal High-voltage rectifier. Same Characteristics as 1B3GT. Has filament-plate shorting protection. Many listed and labeled as 1J3GT/1K3GT. •
1K3GT – Octal High-voltage rectifier. Same Characteristics as 1B3GT. Has filament-plate shorting protection. Many listed and labeled as 1J3GT/1K3GT. •
1S2A – Noval High-voltage rectifier with 1.4 V/550 mA filament. Similar to DY86, DY87, DY802, 1R10, and 1R12. •
1T2 = R16 – Subminiature High-voltage rectifier with 1.4 V/140 mA filament. Has flexible leads. •
1V2 – High-voltage rectifier with 0.625 V/300 mA filament, Miniature 7-pin base •
1X2 – Noval High-voltage rectifier with 1.25 V/200 mA filament. 1X2A, 1X2B and 1X2C have X-Radiation Shielding. Similar to DY80 and R19. •
1Y2 – 4 pin High-voltage rectifier with 1.5 V/290 mA filament. 50KV max PIV, 10mA peak, 2mA average. Usable up to 1 MHz. •
1Z1 – Octal High-voltage rectifier with 0.7 V/180 mA filament. •
1Z2 – Noval High-voltage rectifier with 1.25 V/265 mA filament. •
1AD2 – Compactron High-voltage rectifier with 1.25 V/200 mA filament. Type 1AD2A has X-Radiation Shielding. •
1AJ2 – Compactron High-voltage rectifier with 1.25 V/200 mA filament •
1AY2 – 2-pin "Duopin" base High-voltage rectifier. Has similar electrical characteristics as 1B3GT. •
1B3GT – Octal High-voltage rectifier diode with 1.25 V filament common in monochrome TV receivers of the 1950s and early 1960s. Peak inverse voltage of 30 kV. Anode current 2 mA average, 17 mA peak. Derived from the earlier industrial type 8016. Many listed and labeled as 1B3GT/1G3GT. •
1BC2 – Noval High-voltage rectifier with 1.25 V/200 mA filament. Types 1BC2A and 1BC2B have X-Radiation Shielding. •
1BG2 – Subminiature High-voltage rectifier with 1.4 V/575 mA filament. Has flexible leads. •
1BQ2 – Noval High-voltage rectifier with 1.4 V/600 mA filament •
1BY2 – Compactron High-voltage rectifier with 1.25 V/200 mA filament. Type 1BY2A has X-Radiation Shielding.
2 volt heater/filament tubes 2.5 volt AC heater tubes Tubes used in AC-powered radio receivers of the early 1930s •
2A3 – Directly heated power triode, used for AF output stages in 1930s–1940s audio amplifiers and radios. •
2A5 – Power Pentode (Except for heater, electronically identical to types
42 and
6F6) •
2A6 – Dual diode, high-mu triode (Except for heater, electronically identical to type
75) •
2A7 – Dual-tetrode-style
pentagrid converter (Except for heater, electronically identical to types
6A7,
6A8 and
12A8) •
2B7 – Dual diode and remote-cutoff pentode (Except for heater, electronically identical to type
6B7) •
2E5 and
2G5 – Electron-ray indicators ("Eye tube") with integrated control triode. (Except for heater, electronically identical to types
6E5 and
6G5)
CRT anode rectifiers •
2X2 – High Vacuum High Peak inverse voltage diode, used as rectifier in
CRT EHT supplies. Similar to 1B3 and 1S2 except for heater voltage.
3 volt heater/filament tubes •
3A3/3B2/3AW3 - High Voltage rectifier. An octal type used in color television sets. The heater power is 3.15 volts and 0.22 amps. •
3CA3 - High Voltage rectifier. An octal type used in color television sets. The heater power is 3.6 volts and 0.225 amps. •
3CN3 - High Voltage rectifier. An octal type used in color television sets. The heater power is 3.15 volts and 0.48 amps. The large current is for the advantage of fast warm-up. •
3CU3 - High Voltage rectifier. An octal type used in color television sets. The heater power is 3.15 volts and 0.28 amps. •
3CZ3 - High Voltage rectifier. An octal type used in color television sets. The heater power is 3.15 volts and 0.48 amps. The large current is for the advantage of fast warm-up. •
3AT2 - High Voltage rectifier. A compactron used in television sets to supply power to the anode of the picture tube. It comes in the variation as the 3AT2B, mainly for color television sets with a large picture tube. The 3AT2B comes with X-radiation shielding on the inside. The heater power is 3.15 volts and 0.22 amps. •
3AW2 - High Voltage rectifier. A compactron used for color and black and white television sets. It comes in the variation as the 3AW2A as a replacement for the 3AW2 after the 1967 General Electric X-radiation scandal. The 3AW2A comes with X-radiation shielding on the inside. The heater power is 3.15 volts and 0.22 amps. •
3BF2 - High Voltage rectifier. A compactron used in television sets to supply power to the anode of the picture tube. This tube is very rare, and very special, because it implements an indirectly heated cathode, not connected to the filament. No data is found on this tube, except for the filament power (which is 3.6 volts, 0.225 amps) and the base (which is the 12GQ type). The only reason why we know it is a high voltage rectifier is that the base tells us so. •
3BL2 - High Voltage rectifier. A compactron used in television sets to supply power to the anode of the picture tube. It comes in the variation as the 3BL2A as a replacement for the 3BL2 after the 1967 General Electric X-radiation scandal. The 3BL2A comes with X-radiation shielding on the inside. The heater power is 3.3 volts and 0.285 amps. •
3BM2 - High Voltage rectifier. A compactron used in television sets to supply power to the anode of the picture tube. It comes in the variation as the 3BM2A as a replacement for the 3BM2 after the 1967 General Electric X-radiation scandal. The 3BM2A comes with X-radiation shielding on the inside. The heater power is 3 volts and 0.3 amps. •
3BN2 - High Voltage rectifier. A compactron used for color television sets. It comes in the variation as the 3BN2A as a replacement for the 3BN2 after the 1967 General Electric X-radiation scandal. The 3BN2A comes with X-radiation shielding on the inside. The heater power is 3.15 volts and 0.22 amps. •
3BS2 - High Voltage rectifier. A compactron used for color television sets. It comes in the variation as the 3BS2A and 3BS2B as a replacement for the 3BN2 after the 1967 General Electric X-radiation scandal. The 3BS2A and 3BS2B tubes are identical, maybe a small difference in ratings and characteristics. We do not know these differences as the 3BS2B tube data is not available. The 3BS2A and 3BS2B comes with X-radiation shielding on the inside. The heater power is 3.15 volts and 0.48 amps. The large current is for the advantage of fast warm-up. •
3BT2 - High Voltage rectifier. A compactron used for color television sets. It comes in the variation as the 3BT2A as a replacement for the 3BT2 after the 1967 General Electric X-radiation scandal. The 3BT2A comes with X-radiation shielding on the inside. The heater power is 3.15 volts and 0.48 amps. The large current is for the advantage of fast warm-up. •
3BW2 - High Voltage rectifier. A compactron used for color and black and white television sets. The 3BW2 comes with X-radiation shielding on the inside. It also comes with diffusion bonded cathode (a type of cathode that prevents the back-emission of the anode). This tube was designed in December 1970, after the 1967 General Electric X-radiation scandal. All high voltage rectifier tube types that were designed before 1967 had no X-radiation protection internally. That is why all these tubes made during and after 1967 have a suffix showing they had internal X-radiation protection. This is why there is no '3BW2A' type since it was made after 1967. The heater power is 3.15 volts and 0.22 amps.
5 volt heater/filament tubes •
5R4 – Full wave rectifier •
5U4 – Full wave rectifier •
5V4,
GZ32 – Full wave rectifier •
5Y3 – Full-wave rectifier, octal base version of type
80 •
5AR4,
GZ34 – Full wave rectifier •
5AS4 – Full wave rectifier
6.3 volt heater tubes •
6A6 – Dual Power Triode, used as a
Class-A audio driver or a
Class-B audio output. U7B base. 6.3 volt heater version of type
53 which had a 2.5 volt heater. Octal version –
6N7. •
6A7 and
6A8 (
PH4,
X63) –
Pentagrid converter – dual tetrode style. Based on type
2A7, which had a 2.5 volt heater. 6A7 has a UX7 base with top cap connection for
control grid (grid 4). 6A8 is octal version with top cap connection for control grid. Loctal version: type
7B8. •
6B6-G – Dual Diode, High-mu Triode. Octal version of type
75. Has top-cap connection for triode grid. Later octal version, type
6SQ7, has under-chassis connection for triode grid. Miniature version:
6AV6. •
6B7 (UX7 base),
6B8 (
EBF32, Octal base) – Dual Diode, Semiremote-cutoff Pentodes with control grid on top cap. Based on type
2B7 which had a 2.5 volt heater. The diode anodes are most commonly used as (second) detectors and AVC rectification in superheterodyne receivers. Because their control grids have both sharp-cutoff and remote-cutoff characteristics, these types were used as I.F. amplifiers with AVC bias to the control grid, and as A.F. amplifiers. These types were also used in
reflex radios. In a typical 2B7/6B7/6B8 reflex circuit, the I.F. signal from the converter is injected into the pentode and is amplified. The diodes then act as detectors, separating the A.F. signal from the R.F. signal. The A.F. signal is then re-injected into the pentode, amplified, and sent to the audio output tube. •
6C4/EC90 – 3.6 W small-power V.H.F. triode up to 150 MHz; single
12AU7/ECC82 system •
6C6 – Sharp-cutoff R.F. Pentode. Most common commercial uses were as a tuned R.F. amplifier, a detector, and an A.F. amplifier. Also used in test equipment. Has UX6 base with top cap. Based on type
57, which had a 2.5 volt heater. Similar to types
1603,
77 and octal types
6J7 and
6SJ7 •
6C10 –
Compactron High-mu triple triode, 12-pin base –
not related to the
Mazda/EdiSwan 6C10 triode-hexode •
6D4 – 25 mAavg, 100 mApeak Indirectly heated, argon triode
thyratron, negative starter voltage, 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 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 – Remote-Cutoff R.F. Pentode. Most common commercial uses were as an I.F. amplifier or as a superheterodyne mixer, aka 1st detector. Also used in test equipment. Has UX6 base with top cap. Based on type
58, which had a 2.5 volt heater. Similar to type
78. Octal version:
6U7-G. •
6D8-G –
Pentagrid converter, similar to type
6A8. Octal base with top cap. Has 150 mA heater. Used in pre-war 6-volt
farm radios. •
6D10 – High-mu triple triode for use as oscillator, mixer, amplifier or AFC tube, 12-pin base •
6E5 – "Magic Eye" Tuning indicator. Has incorporated driver triode with sharp-cutoff grid which makes it extremely sensitive to any changes in signal strength. Has UX6 base. Based on type
2E5, which had a 2.5 volt heater. •
6F4 –
Acorn UHF triode up to 1.2 GHz, for use as an oscillator •
6F5 – High-mu triode, equal to triode section of type
6Q7 •
6F6 (
KT63) – Power Pentode. Octal base version of type
42. Moderate power output rating – 9 watts max. (Single-ended Class-A circuit); 11 watts max. (Push-pull Class-A circuit); 19 watts max. (push-pull
Class-AB2 circuit). Available in metal (numbered "6F6"), shouldered glass ("6F6-G"), and cylindrical glass ("6F6-GT"). Sometimes used as a transformer-coupled audio driver for types
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. •
6F7 – Remote-cutoff Pentode, Medium-mu Triode. Has UX7 base with top-cap connection for the pentode's control grid (grid 1). Most common uses were as superheterodyne mixer ("first detector") and local oscillator, or as a combination I.F. amplifier (pentode) and (second) detector or A.F. amplifier (triode). Octal version:
6P7-G. •
6G5 – "Magic Eye" Tuning indicator. Has incorporated triode with remote-cutoff grid, which makes it less reactive to low-level changes in signal strength. Has UX6 base. Electronically identical to type
6U5 except for indicator. Both types had "pie wedge" shadow indicators. At first, the shadow indicator for type 6G5 was fully closed at zero signal and opened as signal strength increased. For type 6U5, the shadow indicator was fully open at zero signal and closed as signal strength increased. After World War II, type 6G5 was discontinued as a unique tube and all 6U5s were double-branded either as
6G5/6U5 or
6U5/6G5. •
6G6-G – Power pentode. Octal base. Low power output – 1.1 watt max. output. Has 150 mA heater. Used in pre-war 6-volt
farm radios. Miniature version –
6AK6. •
6G8-G – Dual Diode, Sharp-cutoff Pentode (Used as Detector and first A.F. stage in Australian 1940s radios) •
6H6,
D63,
EB34,
OSW3109 – Dual diode. Octal base. Most commonly found as a "stubby" metal envelope tube. Glass versions
6H6-G and
6H6-GT are also found. •
6J5 (Metal),
6J5GT (Glass Tubular),
L63 – Heater cathode type, medium-mu triode, identical to 12J5 except heater characteristics :*
6J5WGT – Premium version of 6J5GT, identical to 12J5WGT except heater characteristics •
6J6 – Dual general purpose VHF triode with common cathodes, operates over much of the UHF band (up to 600 MHz), equivalent to ECC91 •
6J7,
EF37 – Sharp-cutoff Pentode. Most common commercial uses were as a tuned R.F. amplifier, a (second) detector, or an A.F. amplifier. Octal version of type
77. This type included a top-cap connection for the control grid. Later version, type
6SJ7, had its control grid connection on pin 4. •
6J8-G – Triode-Heptode (radio local oscillator/mixer) •
6K6-G – Power Pentode, octal version of type
41. Low-to-moderate power output rating – 0.35 to 4.5 watts (single-ended Class-A circuit); 10.5 watts max. (push-pull Class-A circuit). •
6K7,
EF39 – Remote-cutoff R.F. pentode. Most common commercial uses were as an I.F. amplifier or as a superheterodyne mixer, aka 1st detector. Also used in test equipment. Octal version of type
78. This type included a top-cap connection for the control grid. Later version, type
6SK7, had its control grid connection on pin 4. •
6K8 and
12K8 – American Triode-Hexode mixer, 1938 •
6K11 –
Compactron 2x High-mu + 1x medium-mu triple triode, 12-pin base •
6L4 –
Acorn UHF triode for use as an oscillator •
6L5-G – Medium-mu triode (Similar to type 6J5-G, available only in ST shape) •
6L6 (EL37) – High-powered beam tetrode. ::There are several variations. Except for types 6L6-GC and 6L6-GX, all have the same maximum output ratings: ::*11.5 watts (single-ended Class-A circuit) ::*14.5 watts (push-pull Class-A circuit) ::*34 watts (push-pull Class-AB1 circuit) ::*60 watts (push-pull Class-AB2 circuit) ::
6L6 (metal envelope) and
6L6-G (shouldered glass envelope) were used in pre-World War II radios and Public Address amplifiers. ::
6L6 and
25L6 were introduced in 1935 as the first beam 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. (Type
6W6-GT is the 6.3 volt heater version of types
25L6-GT and
50L6-GT.) :*
6L6GA – Post-war version of type 6L6-G, in smaller ST-14 shape with
Shouldered Tubular, (ST), shaped bulb, revision A. :*
6L6GB – Post-war improved version in a cylindrical glass envelope. Similar to type
5881. ::*
6L6GTB – 6L6 with
Tubular, (T), shaped bulb, revision B, (higher power rating, as it happens. The 6L6GTB can always replace the 6L6, 6L6G, and 6L6GT, but a 6L6GTB running at maximum rating should not be replaced with another subtype). ::*
6L6-WGB – "Industrial" version of type 6L6GB. :*
6L6GC – Final and highest-powered audio version of the tube. Max. outputs: ::*17.5 watts (single-ended Class-A circuit) ::*32 watts (push-pull Class-A circuit) ::*55 watts (push-pull Class-AB1 circuit) ::*60 watts (push-pull Class-AB2 circuit) :*
6L6-GX – Class-C oscillator/amplifier used in transmitters. Max. output 30 watts. (All versions may be used as a Class-C oscillator/amplifier, but this version is specifically designed for this purpose, has a special ceramic base.) •
6L7 –
Pentagrid converter often used in console radios of the late 1930s. Similar in structure to pentode-triode pentagrid converters
6SA7 and
6BE6, except that a separate oscillator – usually type
6C5 – is required. Also, grid 1 is remote-cutoff control grid, grid 3 is oscillator input grid. (In types 6SA7 and 6BE6, grid 1 is the internal oscillator grid, grid 3 is the control grid.) Because of low conversion
transconductance, radios using type 6L7 typically have either a tuned RF pre-amplifier stage, or at least two stages of I.F. amplification. (A few models have both.) •
6M5 – Audio Output Pentode (Used as Class-A or C output stages of 1950s Australian radiograms) similar to 6BQ5 •
6M11 –
Compactron Dual triode and pentode •
6N3,
EY82 – Half-Wave Rectifier •
6N5 – Tuning indicator •
6N7 – Dual Power Triode, used as Class-A audio driver or as Class-B power output (also 6N7-G and 6N7-GT). Max. output (Class-B) – 10 watts. Octal version of type
6A6. •
6N8,
EBF80 – Remote-cutoff pentode, dual diode. (detector plus RF or AF amplifier in radios) •
6P5-G/GT – Medium-mu triode, Octal version of type
76, often used as driver for type 6AC5-G. •
6P7-G – Rarely seen octal version of type
6F7. •
6Q5-G – Triode gas
thyratron used in
DuMont oscilloscopes as a sweep generator. Identical to type 884. •
6Q11 – Medium-mu triple triode, 12-pin base, for use as a sync clipper and gated AGC amplifier in TV receivers •
6R3,
EY81 – TV "Damper/Efficiency" Diode •
6R7 – Dual Diode, Medium-mu Triode (also 6R7-G and 6R7-GT). Octal base with top cap. Miniature version –
6BF6. Amplification factor: 16. •
6S7-G – Remote-cutoff RF Pentode, similar to type
6K7. Octal base with top cap. Has 150 mA heater. Used in pre-war 6-volt
farm radios. •
6S8-GT – Triple Diode, High-mu Triode. Octal tube with top-cap connection to triode grid. Has three identical diodes – two diodes share a cathode with the triode, one has a separate cathode. Used as a combined AM detector/AVC rectifier/FM ratio detector/A.F. amplifier in AM/FM radios. Typically, all sections of this tube are arranged around a single heater. •
6T5 – "Magic Eye" Tuning indicator. Has incorporated driver triode with remote-cutoff grid. Has UX6 base. Shadow indicator is fully closed at zero signal. As signal increases, shadow grows outward from the center, covering the entire circumference of the indicator. Electronically identical to types
6G5 and
6U5, which may be used as substitutes. •
6T7-G – Dual diode, high-mu triode, similar to type
6Q7. Octal base with top cap. Has 150 mA heater. Used in pre-war
farm radios. • '''''' – Triple Diode, High-mu Triode. Has three identical diodes – two have cathodes connected to the triode's cathode, one has a separate cathode. Triode amplification factor: 70. Used as an AM detector/AVC rectifier/FM ratio detector/A.F. amplifier in North American AM/FM radios. Identical to type
6AK8/EABC80, but with a shorter glass envelope. •
6U5 (UX6 base),
6U5G (Octal base) – "Magic Eye" Tuning indicator. Has incorporated driver triode with remote-cutoff grid. Has "pie wedge" shadow indicator that is open at zero signal and closes as signal increases. Electronically identical to types
6G5 and
6T5 and may be used as a substitute for those types. After World War II, most new 6U5s were double-branded as either
6G5/6U5 or
6U5/6G5. •
6U7-G – Remote-cutoff R.F. Pentode. Most common commercial uses were as an I.F. amplifier or as a superheterodyne mixer, aka 1st detector. Also used in test equipment. Octal version of type
6D6. Most direct substitute:
6K7. Similar to types
58,
78 and
6SK7. •
6U8A – Triode-pentode, Noval base. Audio preamplifier. •
6U10 – 1x High-mu + 2x medium-mu triple triode, 12-pin base •
6V4 (
EZ80) – Noval-base, indirectly heated, full-wave rectifier. EZ80 rated at 90mA, but 6V4 only rated for 70. Some brands were identical. •
6V6 – Beam power tetrode, used in single-ended Class-A audio output stages of radios and sometimes seen in Class-B audio amplifiers (see also:
5V6 and
12V6). Electrically similar to 6AQ5/EL90. :*
6V6G – 6V6 with
Shouldered Tubular, (ST), shaped bulb. :*
6V6GT – 6V6 with
Tubular, (T), shaped bulb. •
6V7-G – Dual diode, Medium-mu Triode. Octal version of type
85. Amplification factor: 8.3. Similar to type
6R7. •
6W6-GT – Beam power pentode, used most often as a Vertical Deflection Output tube in monochrome TV receivers of the 1950s. Can also be used as an Audio Output tube. This is the 6.3 volt heater version of types
25L6-GT and
50L6-GT. •
6X4 (
EZ90) and
6X5 (
EZ35) – Full-wave rectifiers with indirectly heated common cathode. Type 6X4 has a 7-pin miniature base, the 6X5 has an octal base. Based on type
84/6Z4. No longer in production. •
6AB4/EC92 –
High-mu triode (Pinout same as 6C4 except for pin 5 not having a connection) •
6AB5/6N5 – "Magic Eye" cathode ray
tuning indicator •
6AC5-G – High-mu Power Triode •
6AC7,
1852 – TV sharp-
cutoff R.F. Pentode. (Often encountered in a black metal envelope, not to be confused with the
6CA7.) •
6AC10 –
Compactron High-mu triple triode for use as
NTSC chroma signal demodulator matrix in analog
color TV receivers, 12-pin base •
6AD6-G and
6AF6-G – "Magic Eye" tuning indicators. Both have two "pie wedge" shadow indicators, one each on opposite sides of a single circular indicator target. Both shadows may be used in tandem or may be driven by two different signal sources. Type
6AE6-G is specifically made to drive each indicator with different signals. May also be driven by separate pentodes with different characteristics. E.g., a sharp-cutoff pentode like a
6J7 – which would be hyper-sensitive to any signal change – would drive one shadow, while a remote-cutoff pentode like a
6K7 – which would only react to stronger signals – would drive the other shadow. Both tubes have octal bases. Type 6AD6-G, with a target voltage rated from 100 to 150 volt, is designed for AC/DC radios. Type 6AF6-G, with a target voltage rated at 250 volt, is designed for larger AC radios. •
6AE6-G – A driver triode specially designed for "Magic Eye" tuning indicator types
6AD6-G and
6AF6-G. Has a common heater and indirectly heated cathode, two internally connected triode grids – one with sharp-cutoff characteristics, one with remote-cutoff characteristics – and two anodes, one for each grid. The sharp-cutoff grid reacts to any signal change, while the remote-cutoff grid reacts only to stronger signal changes. •
6AE7-GT – Dual Triode with a common, single anode, for use as a power triode driver •
6AF4 – UHF Medium-mu Triode, commonly found in TV UHF tuners and converters. •
6AF11 –
Compactron High-mu dual triode and sharp-cutoff pentode •
6AG11 –
Compactron High-mu dual triode and dual diode •
6AH5-G – Beam power tube for early TV use. Same as type
6L6-G, but with scrambled pinout. Used in some
Philco receivers. •
6AK5,
EF95, 5654, CV4010, 6J1P (6Ж1П) – Miniature V.H.F. Sharp-cutoff pentode (Used in old
Radiosonde weather balloon transmitters, receiver front ends and contemporary audio equipment), Miniature 7-pin base •
6AK6 – Power pentode. 7-pin miniature version of type
6G6-G. Unusual low-power consumption output tube with 150 mA heater. •
/EABC80 – Triple Diode, High-mu Triode. Diodes have identical characteristics – two have cathodes connected to the triode's cathode, one has a separate cathode. Used as a combination AM detector/AVC rectifier/FM ratio detector/A.F. amplifier in AM/FM radios manufactured outside of North America. Triode amplification factor: 70. North American type
6T8 is identical (but for a shorter glass envelope) and may be used as a substitute. •
6AK9 –
Compactron 1x high-mu + 1x medium-mu dual triode and beam power pentode, 12-pin base •
6AK10 –
Compactron High-mu triple triode for use as NTSC chroma signal demodulator matrix in analog color TV receivers, 12-pin base •
6AL3,
EY88 – TV "Damper/Efficiency" Diode •
6AL5,
EAA91,
D77 – Dual Diode, Detector. Often used in
vacuum tube volt meters (VTVMs). Miniature version of type
6H6. •
6AL6-G – Beam power tube for early TV use. Same as type
6L6-G, but with scrambled pinout and anode connected to top cap. •
6AL7-GT – Tuning indicator used in many early AM/FM Hi-Fi radios. Similar in function to "Magic Eye" tubes. Has two bar-shaped shadows; one grows to indicate signal strength, the other moves to indicate center tuning on FM. •
6AM6,
EF91, Z77 – Sharp-cutoff R.F. pentode used in receiver front ends and test gear such as VTVMs and TV broadcast modulation monitors. •
6AN7, – Triode-Hexode Oscillator/Mixer (radio) •
6AN8, – Triode-Pentode used in frame timebase circuits for television. Electrically fairly similar to ECL80 but with a different pinout. •
6AQ5 – Beam-power pentode, 7-pin miniature similar of type
6V6. •
6AQ8/ECC85 – Dual triode with internal shield. Designed for use as oscillator and mixer in FM receivers. The heater to cathode insulation is inadequate for use in
cascode operation •
6AR8,
6JH8,
6ME8 –
Beam deflection tubes for use as
NTSC chroma signal demodulators in analog
color TV receivers •
6AS6 – Pentode with a fine-pitched suppressor grid which could serve as a second control grid. Used in radar
phantastron circuits. •
6AS7,
6080 – Dual low-mu Triode, low impedance, mostly used for voltage regulation circuits. •
6AS11 –
Compactron 1x high-mu + 1x medium-mu dual triode and sharp-cutoff pentode, 12-pin base •
6AT6 – Dual Diode, High-mu Triode, miniature version of type
6Q7. Triode amplification factor: 70. •
6AU4 – TV "Damper/Efficiency" Diode •
6AU6,
EF94,
6AU6A – Sharp-cutoff pentode •
6AV6 – Dual Diode, High-mu Triode, miniature version of type
75. Triode amplification factor: 100. (Triode section similar in characteristics to one half of a 12AX7.) •
6AV11 –
Compactron Medium-mu triple triode, 12-pin base •
6AX4 – TV "Damper/Efficiency" Diode •
6AX5 – Full-wave rectifier. Octal base. Similar in structure to type
6X5, but with higher voltage and current ratings which are comparable to those of types
5Y3 and
80. •
6BA6,
EF93, W727, 5790 – Semiremote-cutoff R.F. Pentode (Often encountered in
car radios) •
6BD11 –
Compactron 1x high-mu + 1x medium-mu dual triode and sharp-cutoff pentode, 12-pin base •
6BE6,
EK90, 5750, X727 –
Pentagrid Converter (Often encountered in car radios) •
6BF6 – Dual Diode, Medium-mu triode. Miniature version of octal type
6R7. •
6BF8 – Sextuple diode with a common cathode •
6BG6 – Beam tetrode, anode cap. Used in early TV magnetic-deflection horizontal-output stage. •
6BH11 –
Compactron Medium-mu dual triode and sharp-cutoff pentode •
6BK4 – High Voltage beam Triode (30 kV anode voltage). Used as shunt regulator in color TV receivers and measurement equipment such as high voltage meters •
6BK7 – Dual Triode with Internal shield between each section, used in RF circuits (Similar to
6BQ7) •
6BK8,
EF86, Z729 – Audio Pentode used in
microphone preamplifiers and audiophile equipment •
6BK11 –
Compactron 2x High-mu + 1x medium-mu triple triode preamplifier, 12-pin base; used in some guitar amps made by
Ampeg. •
6BL6 (5836) –
Sutton tube, a reflex klystron used as a 250 mW CW microwave source, 1.6 to 6.5 GHz depending upon an external cavity. 4-pin
peewee base with cavity contact rings and top cap •
6BL8,
ECF80 – General-purpose Triode pentode used in TV, audio and test gear •
6BM6 (5837) – Sutton tube used as a 150 mW CW microwave source, 550 MHz to 3.8 GHz depending upon an external cavity. 4-pin
peewee base with cavity contact rings and top cap •
6BM8,
ECL82 – Triode pentode used as the driver and output stages in audio amplifiers, audio output and vertical output stages in TV receivers and has even been seen in an electronic nerve stimulator. •
6BN6 –
Gated-beam discriminator pentode, used in radar, dual channel oscilloscopes and F.M.
quadrature detectors (cf. 6DT6,
nonode). •
6BQ5,
EL84,(N709) – 5.7 Watts AF Power pentode, noval base •
6BQ6-GT – Beam Power Pentode, used as a Horizontal Deflection Output tube in monochrome TV receivers of the 1950s. Most commonly used in receivers with diagonal screen sizes less than . (However, may be found in some larger models.) Larger receivers often used similar type
6DQ6. Later versions of this tube branded as
6BQ6-GTB/6CU6. •
6BQ7 – Dual RF/VHF triode with internal screen. The two sections can be used independently or in a
cascode stage :*
6BQ7A – Improved 6BQ7 capable of operation at UHF frequencies •
6BU8 – Split Anode TV Sync Separator •
6BX6,
EF80 – Sharp-cutoff RF/IF/Video pentode, noval base •
6BY6 – Similar to type
6CS6, but with higher
transconductance.
3BY6 with a different heater •
6BY7,
EF85,
W719 – Remote-cutoff R.F. Pentode (TV IF) •
6BZ6 – Sharp-cutoff R.F. pentode used in video I.F. circuits of the 1960s. •
6BZ7 – Dual Triode. See
6BK7 •
6CA4,
EZ81 – Full Wave Rectifier •
6CA7,
EL34 – Audio Power Output Pentode •
6CA11 –
Compactron High-mu dual triode and sharp-cutoff pentode •
6CB6 – Remote-cutoff R.F. Pentode used in video I.F. circuits of the 1950s and early 1960s. •
6CG7 – Dual Triode (used in TV and some audio amplifiers including modern solid-state designs often as a cathode follower, similar to 6SN7) •
6CJ6 – Line Output Pentode •
6CL6 – Power pentode •
6CM5,
EL36,
EL360 – Audio and TV Line Output Beam Power Tetrode. •
6CS7 – Double Triode with dissimilar triodes. Used in televisions and tube amplifiers. 6CS7 Tube, Double Triode, Data Sheets | Bergholt.net •
6CW4 –
Nuvistor high-mu VHF triode, most common one in consumer electronics •
6CZ5 – Beam pentode for use in vertical deflection or audio amplifier. In certain applications, it can be used in place of a 6973. •
6DA6,
EF89 – R.F. Pentode used in AM/FM radios manufactured outside North America. •
6DJ8,
ECC88,
E88CC, 6922,
6N23P,
6N11 – Dual Audio and R.F. Triode (often used in TV broadcast equipment, test gear, oscilloscopes and audiophile gear) similar to 6ES8 •
6DQ6 – Beam Power Pentode, used as a Horizontal Deflection Output tube in monochrome TV receivers of the 1950s. Most often found in receivers with diagonal screen measurements larger than . Smaller receivers often used similar type
6BQ6-GT. Also used as Audio Output tubes in Standel guitar amplifiers. Later versions branded as
6DQ6-B/6GW6. •
6DR8,
EBF83 – R.F. pentode which will operate with 12 V anode supply, used as I.F. amplifier in car radios which run directly off the 13.5 volt supply. •
6DS4 –
Nuvistor VHF triode used in TV tuners immediately prior to the introduction of solid state tuning circuits. (
RCA TVs equipped with a 6DS4 tuner bore the trademark "Nu-Vista Vision"); successor of the 6CW4. •
6DS8,
ECH83 – Triode-heptode Local oscillator-Mixer which will operate with 12 V anode supply, used in car radios which run directly off the 13.5 volt supply. •
6DT6 – Quadrature detector used in TV audio circuits of the 1950s and early 1960s; cf. 6BN6,
nonode. •
6DV4 – Medium-mu
Nuvistor triode for UHF oscillators; some versions had a gold-plated envelope •
6DX8 – Triode pentode •
6EM5 – TV Vertical Output Pentode •
6ES6,
EF98 – R.F. pentode which will operate with 12 V anode supply, used as tuned R.F. amplifier in car radios which run directly off the 13.5 volt supply. •
6ES8,
ECC89,
E89CC – Dual Triode used as
cascode R.F. amplifier in TV tuners and V.H.F. receiver front ends, also used as general-purpose dual triode in test gear, similar to 6DJ8 •
6EZ8 – High-mu triple triode, Noval base •
6FH8 – Medium-mu triode and three-anode sharp-cutoff tetrode for use in TV receivers and complex wave generators •
6GK5 – Miniature V.H.F. triode (Used as V.H.F. local oscillator in some T.V. Turret Tuners) •
6GM5 – Beam power pentode, identical to 7591 and 7868 with a Noval base •
6GV8,
ECL85 – Triode Pentode (TV vertical output) •
6GW8,
ECL86 – Audio Triode Pentode (audio, TV vertical output) •
6GY8 – High-mu triple triode for use as oscillator, mixer, RF amplifier or AFC tube, Noval base •
6HS8 – Dual-anode pentode for TV receiver sync separation service or as a two-channel
VCA •
6JU8A – 9 mA, Quad diode, units 1&2 and 3&4 internally series-connected •
6KM8 – Diode and three-anode sharp-cutoff tetrode for use in musical instruments, frequency dividers and complex wave generators •
6LF6 – Beam power tetrode with a duodecar
Compactron base and anode cap, for CRT horizontal-deflection amplifiers •
6MD8 – Medium-mu triple triode for use as
NTSC chroma signal demodulator matrix in analog
color TV receivers, B9E Novar 9-pin base •
6ME5 – "Magic Eye"-type tuning indicator, miniature 7-pin base •
6MK8 – Dual-anode pentode for TV receiver sync separation service or as a two-channel
VCA •
6MJ8 – Medium-mu triple triode for use as NTSC chroma signal demodulator matrix in analog color TV receivers, 12-pin base •
6MN8 – High-mu triple triode for use as NTSC chroma signal demodulator matrix in analog color TV receivers, 12-pin base •
6SA7 – First pentode-triode style
pentagrid converter. Octal type. Miniature version:
6BE6. •
6SB7Y (octal),
6BA7 and
12BA7 (Noval) – VHF pentagrids, 1946 •
6SC7 – High-mu dual triode (Both sections share a single cathode) •
6SK7 – Remote-cutoff pentode (Used in I.F. stages of North American radios) Miniature version:
6BD6 •
6SL7,
ECC35 – Dual triode (Used in TV and general electronics) •
6SN7,
ECC32,
B65,
13D2,
CV1986, 6042 – Medium-mu dual triode (Used in Audio Amplifiers, Hammond Organs and Television; extensive use in World War II radar) Each section is equivalent to a
6J5. Miniature version:
12AU7 •
6SS7 – Remote-cutoff pentode (150 mA heater version of the 6SK7, found in some AA6 radios as both the RF amplifier and first IF). This is the only tube to have a same-letter repetition
"7" prefix Loctal tubes These tubes all have 6.3 volt AC/DC heaters. •
7A4 –
Medium-mu triode, Loctal version of type
6J5, often numbered
7A4/XXL •
7A5 – Beam power pentode, Loctal version of type
6U6GT •
7A6 – Dual detector diode, similar to type
6H6 •
7A7 – Remote-
cutoff pentode, Loctal version of type
6SK7 •
7A8 – The only octode
pentagrid converter produced in America by
Sylvania, 1939. Used mostly in
Philco radios. •
7B4 – High-mu triode, Loctal version of types
6F5 and
6SF5 •
7B5 – Power pentode, Loctal version of types
6K6 and
41 •
7B6 – High-mu triode, dual detector diodes, Loctal version of type
75, similar to types
6AV6 and
6SQ7 •
7B7 – Remote-cutoff pentode •
7B8 –
Pentagrid converter, Loctal version of types
6A7 and
6A8 •
7C4 – High frequency diode •
7C5 – Beam power pentode, Loctal version of type
6V6 •
7C6 – High-mu triode, dual detector diode •
7C7 – Sharp-cutoff pentode •
7E5 – Medium-mu high-frequency triode •
7E6 – Medium-mu triode, dual detector diode, Loctal version of types
6R7 and
6SR7, electronically identical to miniature type
6BF6. •
7E7 – Semiremote-cutoff pentode, dual detector diode, similar to types
6B7 and
6B8 •
7F7 – High-mu dual triode, Loctal version of type
6SL7-GT •
7F8 – Medium-mu VHF triode, used as amplifier or converter •
7G7 – Sharp-cutoff pentode •
7G8 – Sharp-cutoff dual tetrode •
7H7 – Semiremote-cutoff pentode •
7J7 – Triode-heptode converter, similar to type
6J8-G •
7K7 – High-mu triode, dual detector diode, similar to types
6AT6 and
6Q7 •
7L7 – Sharp-cutoff pentode •
7N7 – Dual medium-mu triode, Loctal version of type
6SN7-GT •
7Q7 – Pentagrid converter, similar to type
6SA7 •
7R7 – Remote-cutoff pentode, dual detector diode •
7S7 – Triode-heptode converter •
7T7 – Sharp-cutoff pentode •
7V7 – Sharp-cutoff pentode; 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 rectifier diode •
7X7 – High-mu triode, dual detector diodes on separate cathodes, used as FM discriminator and AF amplifier, often numbered
7X7/XXFM •
7Y4 – Full-wave rectifier •
7Z4 – Full-wave rectifier •
7AB7 – Sharp-cutoff pentode •
7AD7 – Power pentode •
7AF7 – Dual medium-mu triode •
7AG7 – Sharp-cutoff pentode •
7AH7 – Remote-cutoff pentode •
7AJ7 – Sharp-cutoff pentode •
7AK7 – Sharp-cutoff, dual control pentode for computer service. Perhaps the first active device specifically designed for computer use.
12.6 volt heater tubes •
12A5 – Power pentode. UX7 base. Center-tapped 12.6 V/300 mA resp. 6.3 V/600 mA heater. Mostly used in pre-war
car radios. •
12A7 – Power pentode, rectifier diode. Pentode section is similar to type
38. Diode has a low power rating – 120 volt, 30 mA – that limits the number of tubes that can be tied to its B+ circuit. Used in one-tube portable phonographs and a few two- and three-tube radios. Forerunner of such types as
32L7-GT,
70L7-GT and
117L7-GT. UX7 base with top cap. Not related to types
2A7 and
6A7. •
12B4A – Low-mu triode, noval base. •
12J5WGT – Heater cathode type, medium-mu triode, identical to 6J5WGT except heater characteristics •
12K5 – Low-anode voltage tetrode with a
space charge grid •
12U5G – Tuning indicator identical to 6U5G except heater characteristics •
12Z3 – Half-wave rectifier, UX4 base •
12AB5 – Beam Power Tube •
12AC10 –
Compactron High-mu triple triode for use as
NTSC chroma signal demodulator matrix in analog
color TV receivers, 12-pin base •
12AE10 –
Compactron Beam power tube and sharp-cutoff pentode •
12AL5 – Dual diode (similar to
6AL5 except for heater) •
12AT6 – Dual diode/triode (Commonly replaced by
12AV6 in consumer radios) •
12AT7, ECC81, 6060, B309, M8162 –
High-mu dual triode. Commonly used as R.F. amplifier/mixer in VHF circuits. •
12AU7, ECC82, 6067, B329, M8136 – Medium-mu dual triode. Two 6C4/EC90s in one envelope; however, it is only specified as an audio frequency device. Commonly used in audio applications and TV receivers. •
12AV6 – Dual diode/High-mu triode (see also:
6AV6) •
12AV7,
5965 – Medium-mu dual triode. Principally designed for VHF amplifier/mixer operation. •
12AX7, ECC83, 6057, B327, M8137 – High-mu dual triode. Very similar to triode section of 6AV6. Commonly used in high-gain audio stages and as power inverters in class A/B amplifiers. •
12AW7 – See 12DW7 below. Called AW by some, but proper name is DW. •
12AY7 – Dual Triode. Medium gain but low noise, intended for low-level/preamplifier use. •
12AZ7 – Dual Triode. Medium-mu, AF Amplifier, or combined oscillator and mixer, Noval base. •
12BA6 – Remote-cutoff pentode,
6BA6/EF93 with a different heater •
12BE6 –
Pentagrid converter,
6BE6/EK90 with a different heater •
12BH7 – Dual Triode, Medium-mu, designed for use in equipment having series heater-string arrangement. •
12BY7 – Video Amplifier Pentode •
12DT5 – Beam Power Pentode •
12DT6 – Sharp-cutoff pentode •
12DW7/ECC832,
7247 – Dissimilar triodes. One half 12AX7 value, other half 12AU7 value. •
12EG6 – Pentagrid converter, both grids 1 and 3 are sharp-cutoff, has 12.6 volt anode and screen grid voltage, for use in car radios •
12FA6 – Low-anode voltage, car radio version of
12BE6 pentagrid converter •
12FQ8 – Common-cathode, dual split-anode triode for use in musical instruments, frequency dividers and complex wave generators •
12FX8 – Low-anode voltage, triode-heptode converter for car radios •
12GA6 – Similar to type
12FA6, but with lower conversion
transconductance •
12MD8 – Medium-mu triple triode for use as
NTSC chroma signal demodulator matrix in analog
color TV receivers, B9E Novar 9-pin base •
12MN8 – High-mu triple triode for use as NTSC chroma signal demodulator matrix in analog color TV receivers, B12C Duodecar 12-pin base •
12SA7 – Pentagrid converter (Octal version of
12BE6) •
12SK7 – Remote-cutoff Pentode (Octal version of
12BA6) •
12SQ7 – Dual diode, triode (Octal version of
12AV6)
"14" prefix Loctal tubes These tubes all have 12.6 volt AC/DC heaters •
14A4 –
Medium-mu triode, Loctal version of type
12J5 •
14A5 – Beam power pentode •
14A7 – Remote-cutoff pentode, often numbered
14A7/12B7 •
14B6 – High-mu triode, dual detector diode, similar to types
12AV6 and
12SQ7 •
14B8 –
Pentagrid converter, Loctal version of type
12A8 •
14C5 – Beam power pentode, Loctal version of type
12V6-GT •
14C7 – Sharp-cutoff pentode •
14E6 – Medium-mu triode, dual detector diode, Loctal version of
12SR7 •
14E7 – Semiremote-cutoff pentode, dual detector diode, similar to type
12C8 •
14F7 – High-mu dual triode, Loctal version of type
12SL7-GT •
14F8 – Medium-mu VHF triode, used as amplifier or converter •
14H7 – Semiremote-cutoff pentode •
14J7 – Triode-heptode converter •
14N7 – Dual medium-mu triode, Loctal version of type
12SN7-GT •
14Q7 – Pentagrid converter, similar to type
12SA7 •
14R7 – Remote-cutoff pentode, dual detector diode •
14S7 – Triode-heptode converter •
14W7 – Sharp-cutoff pentode •
14X7 – High-mu triode, dual detector diodes on separate cathodes, used as FM discriminator and AF amplifier •
14Y4 – Dual rectifier diode •
14AF7 – Dual medium-mu triodes, often numbered
14AF7/XXD 25 volt series heater tubes •
25A6 – Power pentode, octal version of type
43 •
25C5 – Beam Power Pentode (Identical to the 50C5 but with a 25 V 300 mA heater) •
25F5 – Beam Power Pentode (Identical to the 50C5, but with a 25 V 150 mA heater, used in some AA5 type radios using push-pull output) •
25L6 – Beam-power pentode (Except for heater, electrically identical to type
50L6) •
25Z5 – Dual rectifier diode •
25Z6 – Octal version of
25Z5 35 volt series heater tubes •
35A5 – Beam Power Tube (Loctal, Similar to 35L6) •
35B5 – Beam power tube •
35C5 – Identical to 35B5 except for basing ("pin-out") arrangement (HL92) •
35L6-GT – Beam power pentode similar to, but not electronically identical to, types
25L6-GT and
50L6-GT •
35W4 – Rectifier diode •
35Y4 – Rectifier Diode (Loctal, similar to 35Z5) •
35Z3 – Rectifier Diode (Loctal, Similar to 35Z4) •
35Z4-GT – Rectifier diode •
35Z5-GT – Similar to
35Z4-GT, but equipped with a heater tap used to power a pilot light •
35DZ8 –
High-mu Triode/Beam Power tube (Like the 35HB8, used for audio) •
35HB8 – Triode/Beam Power tube (Used primarily as both the audio amplifier and output)
50 volt series heater tubes •
50A5 – Beam Power Tube (Loctal, similar to 50L6) •
50B5 – Beam power tube, similar to 35B5 but with 50 volt heater •
50C5 – Similar to 35C5 but with 50 volt heater, and
50B5 except for basing ("pin-out") arrangement •
50L6 – Beam power tube (see also
25L6) •
50X6 – Dual Diode (Loctal, commonly used as a rectifier-doubler) •
50DC4 – Rectifier diode (Similar to 35W4 except for heater) •
50EH5 – Beam Power tube, (Similar to 50C5 but with higher gain, some radios that use this tube do not have an audio amplifier section.) •
50HK6 – Power pentode (Filament is tapped for use with a dial lamp)
117 volt heater tubes All of the following tubes are designed to operate with their heaters connected directly to the 117 volt (now 120 volt) electrical mains of
North America. All of them use indirectly heated cathodes. All of them incorporate at least one rectifier diode. • Rectifier diode – Beam power pentode combinations :*
117L7GT :*
117M7GT :*
117N7GT :*
117P7GT • Rectifier tubes :*
117Z3 – Single diode, 7-pin miniature version of
117Z4GT :*
117Z4GT :*
117Z6GT – Dual diode, can be used as a voltage doubler
Other tubes with nonstandard heater voltages The tubes in this list are most commonly used in series-wired circuits. •
5J6 – General purpose RF dual triode with common cathodes, a 6J6 with a 4.7 volt/600 mA controlled warm-up heater •
8B10 –
Compactron Dual triode and dual diode •
2AF4 – UHF triode oscillator •
2BN4 – VHF triode •
2CW4 –
Nuvistor high-mu VHF triode, 6CW4 with a 2.1 volt/450 mA heater; used in TV receivers with series heater strings •
2CY5 – VHF sharp-cutoff tetrode •
2EA5 – VHF sharp-cutoff tetrode •
2EN5 – Dual diode •
2ER5 – VHF triode •
2ES5 – VHF triode •
2EV5 – VHF sharp-cutoff tetrode •
2FH5 – VHF triode •
2FQ5 – VHF triode •
2FV6 – VHF sharp-cutoff tetrode •
2FY5 – VHF triode •
4CB6 – Sharp-
cutoff pentode •
7AU7 –
Medium-mu Dual triode with a center-tapped 7.0/3.5 V heater, like the
12AU7 •
7KY6 – Sharp-cutoff frame-grid pentode with a 7.3 volt nominal heater voltage for use as video output tube in TV receivers, Noval base •
8AC10 –
Compactron High-mu triple triode for use as
NTSC chroma signal demodulator matrix in analog
color TV receivers, 12-pin base •
8FQ7/8CG7 – Dual triode (8 V version of the common
6CG7) •
10DE7 – Dual triode (dissimilar triode sections) •
11DS5 – Beam Power tube (11 V heater version of the
50B5/35B5) •
13CW4 –
Nuvistor used as a
preamplifier in
Neumann condenser microphones U-47 and U-48 after the production of the VF14 ceased •
17EW8, HCC85 – Dual High-mu triode •
18FX6 –
Pentagrid converter (18 V version of the
12BE6) •
18FY6 – Dual diode/triode (18 V version of the
12AV6) •
34GD5 – Beam power tube (34 V version of the
35C5/50C5) •
36AM3 – Half-wave rectifier (36 V version of the
35W4) •
38HE7 –
Compactron Diode and beam power tube •
38HK7 –
Compactron Diode and beam power tube ==List of
RMA professional tubes==