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Tube Tinker — Electron Tube Database
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Specialized - Switching Tube ·Tetrode

GMI29B

Russian high-voltage pulse tetrode for modulator switching.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
12.6 V / 69.5 A

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
12.6 V
Nominal heater current
69.5 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 0

Tetrode

X-ray radiationInterelectrode capacitances
Max plate voltage
30000 V

Pulse switching/modulator service; maximum pulse duration 10 microseconds. Output power is not plate dissipation.

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

2026 Russian Power

Published operating points and test conditions from this source.

SECTION 0

Tetrode

Other

  • Heater/filament voltage

    12.6 V

    Nominal heater voltage

  • Heater/filament current

    69.5 A

    Nominal heater current

  • Maximum plate voltage

    30000 V

    Maximum anode voltage

  • Maximum pulse duration

    10 µs

    Maximum pulse duration as stated in manufacturer mini-datasheet