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Power - Triode (over 1000V 100W) ·Triode

8040

Forced-air-cooled high-mu pulse-switch triode for high-power pulse-modulator switching service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
13 V / 205 A

Description

Forced-air-cooled high-mu pulse-switch triode in the 8038/8040/8041 family.

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
13 V
Nominal heater current
205 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

Triode

X-ray radiationInterelectrode capacitances
Amplification factor
120
Max plate voltage
65000 V
Max plate dissipation
10000 W
Max grid dissipation
1000 W
Max cathode current
175 A

Applicable promoted ratings populated from printed headings; remaining published device-specific data retained as 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

1971 Machlette Laboratories

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Grid-Plate Capacitance

    30 pF

  • Grid-Filament Capacitance

    80 pF

  • Plate-Filament Capacitance

    0.8 pF

Other

  • Filament Starting Current

    800 A

  • Peak Plate Voltage

    65000 V

    Pulse

  • DC Grid Voltage

    -1500 V

  • Pulse Cathode Current

    175 A

    Pulse

  • Pulse Duration

    1000 us

  • Duty Factor

    0.01