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Voltage - Triode (single) ·Triode

GK40

Cold-cathode gas triode for relay, trigger, timing, counting, or automatic control switching.

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

Description

The Ferranti GK40 is a miniature gas-filled cold-cathode triode designed for relay and pulse-control applications.

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

Triode

X-ray radiationInterelectrode capacitances
Max plate voltage
140 V

Cold-cathode relay triode discharge section.

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

1963 Ferranti

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum Anode Voltage

    140 V

  • Maximum Peak Anode Current

    20 mA

  • Maximum Grid/Trigger Current

    0.5 mA

  • Typical Anode Voltage

    135 V

  • Typical Static Bias

    70 V

    Positive

  • Typical Trigger Pulse Amplitude

    20 V

    Approximate/Maximum as source

Characteristics

  • Trigger Voltage

    79-85 V

  • Anode-Cathode Voltage Drop

    73 V

    Approximate

  • Minimum Transfer Current

    4uA minimum text

  • Average Recovery Time

    0.0015 s