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Power - Triode (over 1000V 100W) ·Triode

GMI42B

Russian high-current pulse-power switching triode with large peak-current capability for pulse-modulator service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
26 V / 3.4 A

Description

The GMI42B is a pulse-power switching triode with large peak-current capability.

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
26 V
Nominal heater current
3.4 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

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.0004 S
Max plate voltage
33000 V
Max plate dissipation
500 W
Max grid dissipation
25 W
Max cathode current
9 A

Promoted from published pulse switching limits; non-promoted pulse quantities retained as parameters.

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

1968 Electronintorg

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater current

    3.2 A to 3.6 A

Other

  • Maximum anode voltage

    30000 V

  • Peak anode current

    30 A

  • Peak cathode current

    9 A

  • Negative cutoff/bias voltage

    200 V

  • Peak excess grid voltage

    1400 V

  • Maximum pulse duration

    50 us

  • Pulse 1/duty factor minimum

    33

  • Minimum warm-up time at 30 A

    3 min

  • Minimum warm-up time at 8 A / 25 kV

    2 min

Capacitance

  • Input capacitance maximum

    130 pF

  • Output capacitance maximum

    25 pF

  • Transfer capacitance maximum

    2 pF

Data set 02

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • features anode operating voltage of

    33000 V

    SourcePage1-2

  • Current 3400(± 250) mA 14

    9 min

    SourcePage1-2

  • Heating time

    3 min

    SourcePage1-2

  • Heater-cathode voltage, peak ±

    100 V

    SourcePage1-2

  • Input <

    130 pF

    SourcePage1-2

  • Output <

    25 pF

    SourcePage1-2

  • Feedback <

    2 pF

    SourcePage1-2

Other

  • Anode voltage

    33000 V

    SourcePage1-2

  • Cathode current, pulse (max duration

    50 µS

    SourcePage1-2

  • Grid voltage, negative

    -600 V

    SourcePage1-2

  • Grid voltage, positive (in pulse)

    1400 V

    SourcePage1-2

  • Maximum grid dissipation

    25 W

    SourcePage1-2

  • Anode voltage

    2500 V

    TypicalOperation

  • Grid voltage, negative

    -200 V

    TypicalOperation

  • Grid voltage when switched on, positive

    1350 V

    TypicalOperation

  • Pulse duration

    10 µS

    TypicalOperation

  • Anode current when switched on

    30 A

    TypicalOperation

  • Grid current when switched on <

    4.5 A

    TypicalOperation

  • Pa =

    500 W

    TypicalOperation

  • Svetlana GMI-42B

    300 W

    TypicalOperation

  • Grid Current

    200 W

    TypicalOperation