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Specialized - Switching Tube ·Tetrode

EN40

Cold-cathode pulse tetrode for trigger and switching circuits. Its gas-discharge operation provides rapid heaterless pulse conduction.

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

Description

The Ferranti EN40 is a cold-cathode tetrode stroboscopic light source with whitish high-actinic output.

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

Tetrode

X-ray radiationInterelectrode capacitances
Max plate voltage
440 V

Cold-cathode gas-discharge tetrode 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

Tetrode

Other

  • Maximum Static Anode Voltage

    440 V

  • Maximum Working Anode Voltage

    350 V

  • Maximum Mean Anode Current

    100 mA

  • Maximum Repetition Frequency

    150 Hz

  • Typical Supply Voltage

    300-330 V

  • Trigger Pulse Amplitude

    150 V

    Minimum where specified

  • Charging Resistor

    3500 ohm

  • Peak Inverse Anode Voltage

    300 V

  • Maximum Average Trigger Current

    10 mA

Characteristics

  • Minimum Working Anode Voltage

    250 V

  • Static Trigger/Striking Voltage

    70-120 V

  • Peak Anode Current

    250 A

    Pulse