Data set 01
1956 Western Electric Tubes
Published operating points and test conditions from this source.
SECTION 1
Pentode
Characteristics
Typical Plate Voltage
135 V
Typical Plate Current
5.5 mA
Other
Maximum Power Output
0.25 W
ClassA
Voltage Pentode ·Pentode
348A
Western Electric heater-cathode general-purpose pentode with a 275-volt maximum plate rating.
Directly heatedCold cathodeCommon cathodeDissimilar
- Sections
- 1
- Base
- -
- Socket code
- OCTAL7
- Base pins
- 7
- Nominal heater
- 6.3 V / 500 mA
Description
The Western Electric 348A is a heater-cathode general-purpose pentode with 275 V maximum plate rating.
Socket description
7-contact octal-family base
General specifications
Tube and section characteristics
Properties common to every published source and operating point.
Heater and base
- Base
- -
- Socket code
- OCTAL7
- Base pins
- 7
- Nominal heater voltage
- 6.3 V
- Nominal heater current
- 500 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
- 1400000 Ω
- Transconductance
- 0.00184 S
- Max plate voltage
- 250 V
- Max screen voltage
- 180 V
- Max plate dissipation
- 2.5 W
- Max screen dissipation
- 0.4 W
- Max cathode current
- 10 mA
Promoted from published limiting conditions and representative published characteristics.
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
Capacitance
Control grid to plate
0.025 pF
Control grid to heater/cathode/screen/suppressor grids
6 pF
Plate to heater/cathode/screen/suppressor grids
15 pF
Other
Maximum direct screen-grid current
2.5 mA
Characteristic
Typical plate current
5.6 mA
PlateVoltage=250V;ScreenGridVoltage=135V;ControlGridVoltage=-3V