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Voltage - Triode (single) ·Triode

331

Early Cunningham triode documented for receiving-equipment service; available source metadata does not support a narrower functional assignment without speculation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
4
Nominal heater
2 V / 130 mA

Description

The 331 is a triode described in the Cunningham Radio Tube Manual for detector, amplifier, oscillator, rectifier, or power-output service as applicable to the type.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
4
Nominal heater voltage
2 V
Nominal heater current
130 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
5100 Ω
Transconductance
0.00075 S
Amplification factor
3.8
Max plate voltage
180 V

Core published characteristics promoted conservatively from the approved manual sheet.

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

193X Cunningham

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater/filament voltage

    2 V

    Published nominal

  • Heater/filament current

    130 mA

    Published nominal

  • Transconductance

    750 uS

    Published characteristic

  • Amplification factor

    3.8

    Published characteristic

  • Plate resistance

    5100 Ohm

    Published characteristic