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Voltage Pentode - Remote Cutoff (single) ·Pentode

W31

Variable-mu or remote-cutoff pentode designed for RF, IF, broadband, or AVC-controlled receiver amplification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B7
Base pins
7
Nominal heater
4 V / 1 A

Description

A 0.3-ampere series-heater variable-mu screen pentode for H.F. or I.F. stages in D.C. and universal receivers, with low anode-grid capacitance.

Socket description

Medium 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B7
Base pins
7
Nominal heater voltage
4 V
Nominal heater current
1 A
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
Transconductance
0.00175 S
Max plate voltage
250 V
Max screen voltage
100 V

Published ratings and characteristics promoted from the approved datasheet.

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

1937 Osram Valves

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Heater Voltage

    13 V

    Published datasheet value

  • Heater Current

    300 mA

    Published datasheet value

  • Anode Voltage Maximum

    250 V

    Published datasheet value

  • Screen Voltage Maximum

    100 V

    Published datasheet value

Characteristic

  • Mutual Conductance

    2700 µS

    Published datasheet value