Skip to main content
Tube Tinker — Electron Tube Database
Alternatives & variationsDownload PDF datasheet

Power - Pentode Single (NOT beam) (under 10W) ·Pentode

374A

Western Electric oxide-filament power pentode with published Class-A output characteristics. Its directly heated construction provides low-frequency power amplification from a filamentary cathode.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
7
Nominal heater
3 V / 830 mA

Description

Oxide-filament power pentode with published Class A output characteristics.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
7
Nominal heater voltage
3 V
Nominal heater current
830 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
60000 Ω
Transconductance
0.0034 S
Amplification factor
210
Max plate voltage
150 V
Max screen voltage
150 V
Max plate dissipation
4.8 W
Max screen dissipation
1 W

Transconductance 3400 uS and plate resistance 60 kohm at the 150 V operating point.

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 01

1956 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristic

  • HeaterOrFilamentVoltage

    3 V

  • HeaterOrFilamentCurrent

    530 mA

Other

  • Typical Plate Voltage

    135 V

    ClassA

  • Typical Plate Current

    18 mA

    ClassA

  • Power Output

    1.3 W

    ClassA

Data set 02

2026 Western Electric 300s

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • GridPlateCapacitance

    0.18 pF

  • Input Capacitance

    9.2 pF

  • Output Capacitance

    6.5 pF

Characteristic

  • Plate Current

    24 mA

    Plate=150 V; Screen=150 V; Grid=-18 V

  • Screen Grid Current

    1.2 mA

    Plate=150 V; Screen=150 V; Grid=-18 V

  • Load Resistance

    4000 ohm

    Plate=150 V; Screen=150 V

  • Maximum Signal Power Output

    2 W

    Plate=150 V; Screen=150 V