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

9C25

Forced-air-cooled grounded-grid power triode for communications and industrial RF service. Rated around 17.5 kW plate dissipation, with published operation providing roughly 18 kW RF output and reduced ratings usable to about 100 MHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6 V / 285 A

Description

Forced-air-cooled grounded-grid power triode for communications and industrial RF service, with full ratings through 30 MHz and reduced ratings to 100 MHz.

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
6 V
Nominal heater current
285 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
Max plate voltage
11500 V
Max plate dissipation
17500 W
Max cathode current
4 A

Published ratings and characteristics promoted where clearly applicable; additional published 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

1940 RCA

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater or filament voltage

    6 V

    Published nominal value

  • Heater or filament current

    285 A

    Published nominal value

  • Cooling

    Forced air

    External plate radiator

Other

  • Maximum plate dissipation

    17500 W

    Published maximum

  • Maximum full-rating frequency

    30 MHz

    Full plate voltage, plate input, and grid current

  • Maximum reduced-rating frequency

    100 MHz

    Reduced plate voltage, plate input, and grid current

  • Maximum plate input

    40 kW

    Class B / Class C maximum

  • Typical RF power output

    9.2 kW

    Grounded-filament RF service example

  • Typical RF power output

    18 kW

    Grounded-grid RF service example