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Voltage - Triode (single) ·Triode

231D

Western Electric low-filament-power directly heated triode for professional signal amplification and general electronic service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
MEDIUM4BAYONET
Base pins
4
Nominal heater
3.1 V / 60 mA

Description

The Western Electric 231D is a triode listed in the supplied catalog table.

Socket description

Medium 4-contact bayonet base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
MEDIUM4BAYONET
Base pins
4
Nominal heater voltage
3.1 V
Nominal heater current
60 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
14600 Ω
Transconductance
0.00051 S
Amplification factor
7.8
Max plate voltage
150 V

Promoted fields mapped from published ratings/characteristics; additional published values preserved in parameter table.

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

1933 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate-grid capacitance

    3.2 pF

    Published direct interelectrode capacitance

  • Plate-filament capacitance

    2.5 pF

    Published direct interelectrode capacitance

  • Grid-filament capacitance

    2.4 pF

    Published direct interelectrode capacitance

Data set 02

1956 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Maximum/Typical Power Output

    0.0045 W

    Catalog-table value

Other

  • Maximum Plate Voltage

    150 V

    Catalog-table value

Data set 03

2026 Western Electric 200s

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Filament Voltage

    2.9 Volt

    Filament Voltage 2.9 to 3.4 Volts, DC

  • Average Filament Current

    0.06 Ampere

    Average Filament Current 0.060 Ampere

  • Grid Voltage

    -3 Volt

    Grid Voltage —3.0 —7.5 Volts

  • Average Plate Current

    2 Milliamperes

    Average Plate Current 2 2.5 Milliamperes

  • Average Plate Resistance

    15600 Ohms

    Average Plate Resistance 15,600 14,600 Ohms

  • Average A m p l i fi c a t i o n Factor

    7.8

    Average A m p l i fi c a t i o n Factor 7.8 7.8

  • Filament current

    0.06 ampere

    Filament current 0.060 ampere, d.c.

  • Nominal fi l a m e n t voltage

    3.1 volt

    Nominal fi l a m e n t voltage 3.1 volts

  • characteristics as functions of plate voltage are shown in Figure

    7 volt

    characteristics as functions of plate voltage are shown in Figure 7 for several values of grid voltage.

  • cluded within the area, ABCD, in Figure

    3

    cluded within the area, ABCD, in Figure 3. Amplification factor, plate resistance, transconductance,

  • Microphonic Noise—With a plate voltage of

    90 volt

    Microphonic Noise—With a plate voltage of 90 volts, a grid bias of —3 volts, and a load

  • resistance of

    100000 ohms

    resistance of 100,000 ohms, the mean mic ophonic noise output level of the 231D tube, measured in

  • FILAMENT CURRENT =

    0.06 AMPERE

    FILAMENT CURRENT = 0.060 AMPERE D.C. :iii:S:3SSi

  • FILAMENT CURRENT =

    0.06 AMPERE

    FILAMENT CURRENT = 0.060 AMPERE D.C

Other

  • Plate Voltage

    90 Volt

    Plate Voltage 90 135 Volts Maximum