422A

Western Electric indirectly heated double-diode rectifier for full-wave DC power supplies. Its robust five-volt heater and substantial current capability suit professional high-voltage power-supply service.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: -
Socket code: UX4
Base pins: 8
Nominal heater: 5 V / 3 A

Description

Western Electric 422A is a double diode with indirectly heated cathodes for full-wave rectification and DC power supply service.

Socket description

Medium-shell UX 4-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: -
Socket code: UX4
Base pins: 8
Nominal heater voltage: 5 V
Nominal heater current: 3 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

2 physical sections, each with unique specifications.

Section 1

Rectifier

X-ray radiationInterelectrode capacitances

Rectifier peak inverse voltage: 1800 V
Rectifier nominal output current: 400 mA
Rectifier peak forward current: 900 mA
Rectifier forward voltage drop: 26 V

Representative row for two identical rectifier sections; 0.9 A is published steady-state peak plate current per plate.

Section 2

Rectifier

X-ray radiationInterelectrode capacitances

Rectifier peak inverse voltage: 1800 V
Rectifier nominal output current: 400 mA
Rectifier peak forward current: 900 mA
Rectifier forward voltage drop: 26 V

Second physical rectifier section; electrical properties populated from corresponding identical section.

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

2026 Western Electric 400s

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

Maximum transient peak plate current per plate
4 A
Minimum effective plate supply impedance per plate
100 ohm
Typical DC output current
350 mA
FullWave
Typical DC output voltage
360 V
FullWave
Minimum input choke
10 H
ChokeInputFilter

SECTION 2

Rectifier

Other

Maximum transient peak plate current per plate
4 A
Minimum effective plate supply impedance per plate
100 ohm
Typical DC output current
350 mA
FullWave
Typical DC output voltage
360 V
FullWave
Minimum input choke
10 H
ChokeInputFilter