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Specialized - Thyratron ·Thyratron

FG81A

Inert-gas negative-control thyratron for industrial power control. Grid triggering initiates controlled gas-discharge conduction.

Directly heatedCold cathodeCommon cathodeDissimilarSpecialized
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
2.5 V / 5 A

Description

The FG-81-A is an inert-gas-filled thyratron with a negative control characteristic for applications requiring current flow in the absence of grid excitation over varying 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
2.5 V
Nominal heater current
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

Thyratron

X-ray radiationInterelectrode capacitances
Max plate voltage
500 V
Max cathode current
500 mA

Thyratron. Forward peak anode maximum and average anode current promoted.

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 General Electric Co

Published operating points and test conditions from this source.

SECTION 0

Thyratron

Other

  • Peak Inverse Anode Voltage

    500 V

  • Instantaneous Anode Current

    2 A

    25CyclesAndAbove

  • Surge Anode Current

    40 A

    DesignOnly

Characteristic

  • Peak Voltage Drop

    16 V

    Typical