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

7540

Very-high-power directly heated triode; available source material does not establish a narrower functional application confidently.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
5 V / 250 A

Description

Water-cooled low-mu power triode for zero-drive modulator and audio-frequency service with 35 kW plate-dissipation capability.

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
5 V
Nominal heater current
250 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
5
Max plate voltage
15000 V
Max plate dissipation
35000 W
Max cathode current
10 A

Published ratings and characteristics promoted where clearly applicable; additional source values retained as section 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

1947 Westinghouse

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater or filament voltage

    5 V

    Published nominal/representative value

  • Heater or filament current

    250 A

    Published nominal/representative value

  • Amplification factor

    5

    Published

Other

  • Maximum plate dissipation

    35000 W

    Published

  • Maximum plate input

    70 kW

    Published

Capacitance

  • Grid-to-plate capacitance

    50 pF

    Approximate

  • Grid-to-filament capacitance

    65 pF

    Approximate

  • Plate-to-filament capacitance

    8 pF

    Approximate