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

BR129

Forced-air-cooled tungsten-filament transmitting triode for HF amplifier and oscillator service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
11 V / 125 A

Description

The Marconi BR129 is a forced-air-cooled tungsten-filament transmitting triode for hf amplifier and oscillator service.

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
11 V
Nominal heater current
125 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
0.011 S
Amplification factor
21
Max plate voltage
8500 V
Max plate dissipation
5000 W
Max grid dissipation
600 W

Highest published service maximums promoted; cooling and operating conditions preserved in 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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Heater/filament voltage

    11 V

  • Heater/filament current

    125 A

  • Maximum plate voltage

    8500 V

  • Maximum plate dissipation

    5000 W

  • Maximum grid dissipation

    600 W

  • Maximum frequency at full ratings

    40 MHz

  • Maximum filament starting current

    187 A

Characteristic

  • Amplification factor

    21

  • Transconductance

    11000 uS

Capacitance

  • Grid-plate capacitance

    17.5 pF

  • Plate-cathode capacitance

    27 pF

  • Grid-cathode capacitance

    23.3 pF

Construction

  • Cooling

    Forced air