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Specialized - Thyratron ·Thyratron

GT21

Cold-cathode glow thyratron with grid control for AC or DC switching, using low-level radioactive preionization to stabilize ignition.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
-

Description

Glow thyratron with cold molybdenum cathode, low tritium preionization and grid control; operates from AC or DC anode supplies.

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
-
Nominal heater current
-
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

Thyratron

X-ray radiationInterelectrode capacitances
Max cathode current
40 mA

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

1962 Cerberus

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Characteristics

  • Anode breakdown voltage A-K minimum

    40 V

    UG=-15V

  • Reverse breakdown voltage K-A minimum

    40 V

    UG=0V

  • Auxiliary-cathode breakdown voltage maximum

    -180 V

  • Auxiliary-cathode sustaining voltage maximum

    -110 V

    IHK=-100uA

  • Sustaining voltage A-K

    115 V

    IA=20mA

  • Grid blocking voltage

    -80 to -6 V

  • Grid release voltage

    0.5 to 50 V

Other

  • Cathode current mean

    10 to 40 mA

  • Anode AC supply voltage

    180 to 250 V

  • Anode DC supply voltage

    250 to 350 V