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Power - Triode ·Triode

284A

Low-mu directly heated Western Electric power triode intended for high-current amplifier service. Its approximately 100 W plate dissipation, 1.25 kV plate capability, and low amplification factor suit substantial low-impedance power stages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
J4
Base pins
4
Nominal heater
10 V / 3.25 A

Description

High-power triode for audio amplifier, modulator, and transmitter service.

Socket description

Jumbo 4-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
J4
Base pins
4
Nominal heater voltage
10 V
Nominal heater current
3.25 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
Plate resistance
1900 Ω
Amplification factor
4.7
Max plate voltage
1250 V
Max plate dissipation
100 W
Max cathode current
150 mA

Published ratings and characteristics promoted from the approved datasheet.

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

1933 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate-grid capacitance

    8.2 pF

    Published direct interelectrode capacitance

  • Plate-filament capacitance

    7.8 pF

    Published direct interelectrode capacitance

  • Grid-filament capacitance

    7 pF

    Published direct interelectrode capacitance

Data set 02

2026 Western Electric 200s

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Plate To Grid Capacitance

    8.2 pF

  • Plate To Filament Capacitance

    7.8 pF

  • Grid To Filament Capacitance

    7 pF