Data set 01
1961 Tung Sol
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristic
Heater Warmup Time
11 s
Voltage Pentode - Sharp Cutoff (single) ·Pentode
4AU6
Sharp-cutoff pentode designed for RF, VHF/UHF, wide-band, or voltage-amplifier service.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- 7BK
- Socket code
- B7G
- Base pins
- 7
- Nominal heater
- 4.2 V / 450 mA
Description
Sharp-cutoff miniature pentode for RF amplification in high-frequency wide-band equipment and for FM limiter service.
Socket description
Miniature 7-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- 7BK
- Socket code
- B7G
- Base pins
- 7
- Nominal heater voltage
- 4.2 V
- Nominal heater current
- 450 mA
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
7BK - Terminal pinout
Electrical assignments shared by every tube using this base designation.
| Terminal | Section | Connection | Evidence |
|---|---|---|---|
| PIN1G1 | A | G1 — Control Grid EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN2G3 | A | G3 — Suppressor GridGroup 7BK2 EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN2IS | A | IS — Internal ScreenGroup 7BK2 EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN3H | — | H — Heater EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN4H | — | H — Heater EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN5P | A | P — Plate (Anode) EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN6G2 | A | G2 — Screen Grid EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
| PIN7K | A | K — Cathode EIA chart transcription; independent manufacturer confirmation pending | Unverified EIA Base Connections, printed page 128, 7BK |
Section ratings
1 physical section, each with unique specifications.
Section 1
Pentode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 500000 Ω
- Transconductance
- 0.0045 S
- Amplification factor
- 36
- Max plate voltage
- 300 V
- Max screen voltage
- 300 V
- Max plate dissipation
- 3 W
- Max screen dissipation
- 0.65 W
- Rectifier max heater-cathode voltage
- 180 V
- Rectifier warm-up time
- 11 s
Reference/equivalence-only source: ratings/characteristics for this section are not reproduced; missing promoted values intentionally not inferred from the external 6AU6-A datasheet.
Source-dependent data
Operating conditions by source
Each block preserves the test conditions and published values from one reference. Values from different sources are intentionally kept separate.
Data set 02
1965 Sylvania Electronic Tubes Vol3
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristics
Plate voltage
250 V
PentodeConnection
Screen-grid voltage
125 V
PentodeConnection
Cathode resistor
100 Ohm
PentodeConnection
Transconductance
4500 uS
PentodeConnection
Plate resistance
1500000 Ohm
PentodeConnection
Plate current
7.6 mA
PentodeConnection
Screen-grid current
3 mA
PentodeConnection
Triode-connected plate voltage
250 V
TriodeConnection
Triode-connected amplification factor
36 ratio
TriodeConnection
Triode-connected plate resistance
7500 Ohm
TriodeConnection
Capacitance
Grid-to-plate capacitance
0.0035 pF
PentodeConnection
Input capacitance
5.5 pF
PentodeConnection
Output capacitance
5 pF
PentodeConnection
Data set 03
1966 Tung Sol Electronic Tubes 1 of 4
Published operating points and test conditions from this source.
SECTION 1
Pentode
Capacitance
Grid-to-plate capacitance maximum
0.0035 pF
Section1
Input capacitance
5.5 pF
Section1
Output capacitance
5 pF
Section1
Other
Plate voltage
250 V
ClassA
Screen voltage
150 V
ClassA
Control-grid voltage
-2 V
ClassA
Plate current
10.5 mA
ClassA
Screen current
4.2 mA
ClassA
Characteristic
Transconductance
5200 µS
Section1
Plate resistance
1 MΩ
Section1
Data set 04
1968 General Electric Co
Published operating points and test conditions from this source.
SECTION 1
Pentode
Other
Heater Voltage
4.2 V
Heater Current
450 mA
Data set 05
1971 RCA HB3 Binder 4 of 7
Published operating points and test conditions from this source.
SECTION 1
Pentode
Other
Heater Current
420 mA to 480 mA
Published nominal ± tolerance
Heater Voltage
4.2 V
At heater current 0.45 A
Warm-Up Time
11 s
Average
Plate Voltage
250 V
Inherited from explicitly referenced 6-volt parent type; heater variant
Screen Voltage
150 V
Inherited from explicitly referenced 6-volt parent type; heater variant
Plate Current
10.6 mA
Inherited from explicitly referenced 6-volt parent type; heater variant
Screen Current
4.3 mA
Inherited from explicitly referenced 6-volt parent type; heater variant
Characteristics
Transconductance
5200 µS
Inherited from explicitly referenced 6-volt parent type; heater variant
Plate Resistance
1 MΩ
Inherited from explicitly referenced 6-volt parent type; heater variant
Data set 06
1975 RCA RC30
Published operating points and test conditions from this source.
SECTION 1
Pentode
Other
Heater Voltage (ac/dc) 3.15 4.2 6.3
12.6 V
Published in approved 6AU6A target entry; Section1
Heater Current 0.6 0.45 0.3
150 mA
Published in approved 6AU6A target entry; Section1
age) 11 11
11 seconds
Published in approved 6AU6A target entry; Section1
Plate Voltage 275
330 V
Published in approved 6AU6A target entry; Section1
Positive value
0 V
Published in approved 6AU6A target entry; Section1
0
0 V
Published in approved 6AU6A target entry; Section1
Plate Dissipation 3.5
3.5 W
Published in approved 6AU6A target entry; Section1
For grid-No.2 voltages up to
165 V
Published in approved 6AU6A target entry; Section1
For grid-No.2 voltages between 165 and
330 V
Published in approved 6AU6A target entry; Section1
D-No
1 V
Published in approved 6AU6A target entry; Section1
Capacitance
Internal Shield
55 pF
Published in approved 6AU6A target entry; Section1
Internal Shield
5 pF
Published in approved 6AU6A target entry; Section1
Grid No.l to Plate, Grid No.2, Grid No.3, and Internal Shield
2.6 pF
Published in approved 6AU6A target entry; Section1
Grid No.l to Cathode and Heater 3
2 pF
Published in approved 6AU6A target entry; Section1
Characteristic
Grid-No.2 Supply Voltage 100 125
150 V
Published in approved 6AU6A target entry; Section1
Cathode-Bias Resistor 330 150 100
68 Ω
Published in approved 6AU6A target entry; Section1
Plate Resistance (Approx.) 0.5 1.5
1 MΩ
Published in approved 6AU6A target entry; Section1
Plate Current 12.2 5 7.6
10.6 mA
Published in approved 6AU6A target entry; Section1
2.1 3
4.3 mA
Published in approved 6AU6A target entry; Section1
of 10 flA —4.2 -5.5
-6.5 V
Published in approved 6AU6A target entry; Section1