Data set 01
1956 Western Electric Tubes
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristic
HeaterOrFilamentVoltage
6.3 V
HeaterOrFilamentCurrent
150 mA
Other
Power Output
23 dBm
ClassA
Voltage Pentode ·Pentode
385A
Octal-base Western Electric pentode with published Class-A characteristics, intended for low-level amplifier service.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- IO
- Base pins
- 6
- Nominal heater
- 6.3 V / 150 mA
Description
Octal-base pentode with published Class A characteristics.
Socket description
International Octal
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- IO
- Base pins
- 6
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 150 mA
- 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
Pentode
X-ray radiationInterelectrode capacitances
- Plate resistance
- 500000 Ω
- Transconductance
- 0.0025 S
- Max plate voltage
- 250 V
- Max screen voltage
- 120 V
- Max plate dissipation
- 1.85 W
- Max screen dissipation
- 0.55 W
- Max cathode current
- 12 mA
Limiting conditions specify plate 250 V, screen grid 120 V and total cathode current 12 mA. Characteristics such as plate resistance and transconductance are supplied primarily as curves rather than a single fixed tabulated value.
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 300s
Published operating points and test conditions from this source.
SECTION 1
Pentode
Other
ControlGridPlateCapacitance
0.02 pF
Input Capacitance
3.6 pF
Output Capacitance
2.4 pF
MaximumSuppressorGridVoltage
120 V
MaximumScreenGridCurrent
5 mA
Maximum Heater Cathode Voltage
30 V