Data set 01
1956 Western Electric Tubes
Published operating points and test conditions from this source.
SECTION 1
Triode
Characteristic
HeaterOrFilamentVoltage
10 V
HeaterOrFilamentCurrent
3.25 A
Power - Triode ·Triode
295A
Medium-mu directly heated Western Electric power triode for Class B audio and RF service. A push-pull pair can deliver roughly 250 W, while its 100 W plate dissipation and high-voltage ratings also support transmitting applications.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- JUMBO4B
- Base pins
- 4
- Nominal heater
- 10 V / 3.25 A
Description
Air-cooled transmitting triode.
Socket description
Super Jumbo 4-pin bayonet
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- JUMBO4B
- Base pins
- 4
- Nominal heater voltage
- 10 V
- Nominal heater current
- 3.25 A
- Parallel heater voltage
- -
- Parallel heater current
- -
- Series capable
- No
Terminal pinout
Electrical assignments shared by every tube using this base designation.
No verified pinout is recorded for this base designation.
Section ratings
1 physical section, each with unique specifications.
Section 1
Triode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 6000 Ω
- Transconductance
- 0.0042 S
- Amplification factor
- 25
- Max plate voltage
- 1250 V
- Max plate dissipation
- 100 W
- Max cathode current
- 175 mA
Characteristics at Eb=1250 V, Ib=80 mA.
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
2026 Western Electric 200s
Published operating points and test conditions from this source.
SECTION 1
Triode
Capacitance
Plate to Grid Capacitance
14.5 pF
Grid to Filament Capacitance
6.5 pF
Plate to Filament Capacitance
5.5 pF
Other
Maximum Direct Grid Current
50 mA
Maximum RF Grid Current
7.5 A
Maximum Frequency at Full Ratings
6 MHz
Direct Plate Voltage
1250 V
ClassB;TwoTubes
Grid Bias
-40 V
ClassB;TwoTubes
Approximate Maximum Output
250 W
ClassB;TwoTubes