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

7899

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
8 V / 130 A

Description

7899 is a Triode device in the supplied Amperex literature. Forced-air-cooled hard-tube modulator designed for pulse application.

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
8 V
Nominal heater current
130 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
0.025 S
Amplification factor
33
Max plate voltage
20000 V
Max plate dissipation
7500 W
Max grid dissipation
500 W
Max cathode current
100 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

    25000 µS

  • Amplification Factor

    33

Other

  • Maximum Plate Voltage

    20000 V

  • Maximum Plate Dissipation

    7500 W

  • Maximum Grid Dissipation

    500 W

  • Maximum Cathode Current

    100 A

Data set 02

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    15000 V

    RF/Industrial

  • Plate current

    70 A

    RF/Industrial

  • Output power

    200000 W

    RF/Industrial

  • Grid voltage

    -500 V

    RF/Industrial

  • Grid current

    15000 mA

    RF/Industrial

  • Pulse output power

    200 kW

    Pulsed

  • Pulse plate current

    70 A

    Pulsed

Capacitance

  • Grid-to-plate capacitance

    27 pF

  • Grid-to-filament capacitance

    45 pF

  • Plate-to-filament capacitance

    0.6 pF