F125A

Federal water-cooled low-mu power triode engineered especially for Class AB audio-frequency modulator circuits. Its 40 kW plate dissipation and 15 kV rating support exceptionally powerful transmitter modulation.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 1
Base: -
Socket code: -
Base pins: -
Nominal heater: 27.2 V / 196.5 A

Description

Federal F-125-A water-cooled low-mu power triode engineered especially for Class AB audio-frequency modulator circuits; 40 kW anode dissipation.

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: 27.2 V
Nominal heater current: 196.5 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: 4.75
Max plate voltage: 15000 V
Max plate dissipation: 40000 W
Max grid dissipation: 3000 W
Max cathode current: 10 A

Highest applicable published maximum ratings promoted; service-specific operating points preserved 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

1962 ITT

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

Amplification factor
4.75

Other

Maximum plate voltage
15000 V
Maximum plate dissipation
40000 W
Maximum cathode/plate current
10 A
Maximum frequency for full ratings
0.02 MHz

Capacitance

Grid-plate capacitance
65 pF
Grid-filament capacitance
90 pF
Plate-filament capacitance
12 pF

Construction

Cooling method
Water

Data set 02

1962 ITT Industrial and Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

FilamentStartingCurrent
300 A
AnodeCoolingMethod
Water
MaximumOperatingFrequency
Audio-frequency use
Maximum Anode Dissipation
40000 W
Absolute maximum / applicable service

Capacitance

GridPlateCapacitance
45 pF
GridFilamentCapacitance
56 pF
PlateFilamentCapacitance
20 pF