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Specialized - Thyratron ·Thyratron

AFX203

Directly heated xenon-filled triode thyratron for stable arc switching over a wide ambient-temperature range, suitable for demanding control equipment.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
25 V / 4 A

Description

The Marconi AFX203 is a directly heated xenon-filled triode thyratron whose control characteristics are relatively insensitive to ambient temperature.

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
25 V
Nominal heater current
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

Thyratron

X-ray radiationInterelectrode capacitances
Max cathode current
17 A

Gas-filled triode thyratron; pulse/ignition ratings retained in 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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Thyratron

Other

  • Filament voltage

    25 V

  • Filament current

    4 A

  • Peak inverse voltage

    300 V

  • Peak forward voltage

    280 V

  • Peak anode current

    17 A

  • Average anode current

    400 mA

  • Warm-up time

    20 s

  • Ambient temperature

    -40 to 65 C

Capacitance

  • Anode-grid capacitance

    1 pF

  • Grid-cathode capacitance

    10.4 pF