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Tube Tinker — Electron Tube Database
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Specialized - Cathode Ray ·CathodeRay

31C2

Six-inch magnetic aluminized cathode-ray tube for radio direction-finding compass display. A uniformly graduated internal compass scale provides direct bearing reference alongside the displayed directional indication.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
B12A
Socket code
-
Base pins
5
Nominal heater
4 V / 720 mA

Description

Six-inch magnetic aluminised cathode-ray tube for radio direction-finding compass display, with uniformly graduated internal compass scale.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B12A
Socket code
-
Base pins
5
Nominal heater voltage
4 V
Nominal heater current
720 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B12A - 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

Cathode Ray

X-ray radiationInterelectrode capacitances
Max plate voltage
10000 V

Magnetic aluminised CRT; 10 kV is design-centre max and 12.5 kV absolute must not be exceeded.

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

1960 Mazda

Published operating points and test conditions from this source.

SECTION 1

Cathode Ray

Other

  • Minimum Anode Voltage

    7500 V

  • AbsoluteMaximumAnodeVoltage

    12500 V

  • Typical Anode Voltage

    9500 V

Characteristics

  • GridAllCapacitance

    4.7 pF