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

B142

Thoriated-tungsten transmitting triode for HF amplification, oscillator, and Class-B modulator service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
10 V / 10 A

Description

The Marconi B142 is a thoriated-tungsten transmitting triode intended for high-frequency amplification, oscillation, and Class-B modulation.

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
10 V
Nominal heater current
10 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
35
Max plate voltage
4000 V
Max plate dissipation
400 W

Highest service rating promoted from the printed class-of-service tables.

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

  • Filament voltage

    10 V

  • Filament current

    10 A

  • Maximum plate voltage

    4000 V

  • Maximum plate dissipation

    400 W

  • Maximum frequency natural cooling

    30 MHz

  • Maximum frequency reduced ratings

    75 MHz

  • Typical plate voltage

    4000 V

    ClassC

  • Typical plate current

    450 mA

    ClassC

  • Typical plate output

    1800 W

    ClassC

Characteristic

  • Amplification factor

    35

Capacitance

  • Grid-plate capacitance

    56 pF

  • Plate-cathode capacitance

    88 pF

  • Grid-cathode capacitance

    14 pF