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

7900

High-power triode designed for pulse-modulator service, with manufacturer ratings centered on short-duration high-voltage, high-current pulses rather than continuous RF or audio operation. Its intended role is switching or modulating pulsed power in professional equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
12.6 V / 32 A

Description

7900 is a Triode device in the supplied Amperex literature. Forced-air-cooled triode for television transmitter operation to 220 MHz with brazed silver-plated radiator.

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
12.6 V
Nominal heater current
32 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
Transconductance
0.015 S
Amplification factor
32
Max plate voltage
6000 V
Max plate dissipation
4000 W
Max cathode current
1.5 A

Published ratings/characteristics promoted from the source; representative section used for repeated identical systems where applicable.

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

1953 Amperex

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Transconductance

    15000 µS

  • Amplification Factor

    32

Other

  • Maximum Plate Voltage

    6000 V

  • Maximum Plate Dissipation

    4000 W

  • Maximum Cathode Current

    1.5 A

Data set 02

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    4500 V

    RF/Industrial

  • Plate current

    1.75 A

    RF/Industrial

  • Output power

    5600 W

    RF/Industrial

  • Grid voltage

    -130 V

    RF/Industrial

  • Grid current

    350 mA

    RF/Industrial

  • Maximum frequency at full input rating

    220 MHz

Capacitance

  • Grid-to-plate capacitance

    18 pF

  • Grid-to-filament capacitance

    17 pF

  • Plate-to-filament capacitance

    0.3 pF