Data set 01
1961 Tung Sol
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
Heater Warmup Time
11 s
Voltage - Dual Triode (similar high frequency) ·Triode-Triode
4BC8
Medium-mu twin triode intended for VHF television tuners, particularly cascode RF amplification, with additional suitability for push-pull cathode-drive RF amplifier circuits.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 2
- Base
- 9AJ
- Socket code
- B9A
- Base pins
- 9
- Nominal heater
- 4.2 V / 600 mA
Description
Medium-mu twin triode used as a cascode amplifier in VHF television tuners and in push-pull cathode-drive RF amplifiers.
Socket description
Small-button Noval 9-contact
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- 9AJ
- Socket code
- B9A
- Base pins
- 9
- Nominal heater voltage
- 4.2 V
- Nominal heater current
- 600 mA
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
9AJ - Terminal pinout
Electrical assignments shared by every tube using this base designation.
| Terminal | Section | Connection | Evidence |
|---|---|---|---|
| PIN12P | B | P — Plate (Anode) Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN22G1 | B | G1 — Control Grid Source label preserved; pending confirmation | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN32K | B | K — Cathode Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN4H | — | H — Heater Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN5H | — | H — Heater Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN61P | A | P — Plate (Anode) Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN71G1 | A | G1 — Control Grid Source label preserved; pending confirmation | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN81K | A | K — Cathode Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
| PIN9IS | A | IS — Internal Screen Numbered source electrode preserved; manufacturer verification pending | Unverified EIA Base Connections, printed page 131, 9AJ |
Section ratings
2 physical sections, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 7500 Ω
- Transconductance
- 0.0062 S
- Amplification factor
- 45
- Max plate voltage
- 250 V
- Max plate dissipation
- 2.2 W
- Max cathode current
- 22 mA
- Rectifier max heater-cathode voltage
- 200 V
- Rectifier warm-up time
- 11 s
Published ratings and characteristics promoted where applicable.
Section 2
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 7500 Ω
- Transconductance
- 0.0062 S
- Amplification factor
- 45
- Max plate voltage
- 250 V
- Max plate dissipation
- 2.2 W
- Max cathode current
- 22 mA
Second identical physical triode section; added to align rows with SectionCount.
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
1966 Tung Sol Electronic Tubes 1 of 4
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Plate voltage
100 V
Cascode;EachSection
Plate current
8.5 mA
Cascode;EachSection
Application
VHF cascode amplifier in television tuners
Section1
Characteristic
Transconductance
6200 µS
EachSection
Plate resistance
7500 Ω
EachSection
Amplification factor
45
EachSection
Data set 03
1971 RCA HB3 Binder 4 of 7
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Heater Current
560 mA to 640 mA
Published nominal ± tolerance
Heater Voltage
4.2 V
At heater current 0.6 A
Warm-Up Time
11 s
Average
Plate Voltage
150 V
Inherited from explicitly referenced 6-volt parent type; heater variant
Cathode Resistor
220 Ω
Inherited from explicitly referenced 6-volt parent type; heater variant
Plate Current
10 mA
Inherited from explicitly referenced 6-volt parent type; heater variant
Characteristics
Amplification Factor
35
Inherited from explicitly referenced 6-volt parent type; heater variant
Plate Resistance
5300 Ω
Inherited from explicitly referenced 6-volt parent type; heater variant
Transconductance
6200 µS
Inherited from explicitly referenced 6-volt parent type; heater variant
Data set 04
1975 RCA RC30
Published operating points and test conditions from this source.
SECTION 1
Triode
Other
Heater Voltage (ac/dc) 4.2
6.3 V
Published in approved 6BZ8 target datasheet entry; Section1
Heater Current 0.6
400 mA
Published in approved 6BZ8 target datasheet entry; Section1
Cathode Current
22 mA
Published in approved 6BZ8 target datasheet entry; Section1
Plate Dissipation
2.2 W
Published in approved 6BZ8 target datasheet entry; Section1
Cathode-Bias Resistor
220 Ω
Published in approved 6BZ8 target datasheet entry; Section1
Plate Resistance (Approx.)
5300 Ω
Published in approved 6BZ8 target datasheet entry; Section1
Plate Current
10 mA
Published in approved 6BZ8 target datasheet entry; Section1
Grid Voltage (Approx.) for transconductance of
50 µS
Published in approved 6BZ8 target datasheet entry; Section1
Grid Voltage (Approx.) for transconductance of 50 /imhos
-13 V
Published in approved 6BZ8 target datasheet entry; Section1
Capacitance
Grid to Plate 1.2
1.2 pF
Published in approved 6BZ8 target datasheet entry; Section1
Plate to Grid, Heater, and Internal Shield
2.4 pF
Published in approved 6BZ8 target datasheet entry; Section1
Plate to Cathode
0.12 pF
Published in approved 6BZ8 target datasheet entry; Section1
Heater to Cathode 2.8
2.8 pF
Published in approved 6BZ8 target datasheet entry; Section1