12H31

Heptode frequency converter for superheterodyne receiving equipment. Its multi-grid construction combines local oscillator and mixer functions, translating incoming radio-frequency signals to the receiver intermediate frequency.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: B7G
Base pins: 7
Nominal heater: 12.6 V / 150 mA

Description

150 mA series-heater mixer heptode for radio receiver frequency-converter service.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: B7G
Base pins: 7
Nominal heater voltage: 12.6 V
Nominal heater current: 150 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

Heptode

X-ray radiationInterelectrode capacitances

Max plate voltage: 300 V
Max screen voltage: 100 V
Max plate dissipation: 1 W
Max screen dissipation: 1 W
Max cathode current: 14 mA

Tesla 12H31 indirectly heated variable-mu heptode frequency-changer mixer, heater 12.6 V at 150 mA. Maximum cathode current 14 mA. Manufacturer maximum plate voltage 300 V, screen voltage 100 V, plate and screen dissipation 1 W each. Conversion conductance about 0.455–0.475 mA/V at specified mixer operating points is converter-specific and should not be represented as intrinsic static gm. Interelectrode capacitances explicitly published.

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

1969 Tesla Manual of Electronic Tubes

Published operating points and test conditions from this source.

SECTION 1

Heptode

Characteristics

Heater voltage
12.6 V
Published nominal value
Heater current
150 mA
Published nominal value

Other

Maximum plate dissipation
1 W
Published maximum rating
Application
Mixer
Printed source application