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Rectifier - Half Wave ·Rectifier

CX381

Cunningham directly heated half-wave rectifier for early radio power supplies. Its 7.5 V filament and moderate output capability provide conventional receiving-equipment AC-to-DC conversion.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
UX4
Base pins
-
Nominal heater
7.5 V / 1.25 A

Description

CX381: Cunningham power-supply rectifier tube. The complete bulletin was read for construction, ratings, circuit recommendations, and operating characteristics.

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
-
Nominal heater voltage
7.5 V
Nominal heater current
1.25 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

Rectifier

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
700 V
Rectifier nominal output current
85 mA

Published ratings and characteristic constants promoted where applicable; operating recommendations retained as 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

1931 Cunningham Radio Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristics

  • Filament/heater voltage

    7.5 V

  • Filament/heater current

    1.25 A

Other

  • Peak inverse/anode AC voltage

    700 V

  • DC output current

    85 mA

  • AC input voltage

    700 V

    HalfWave

  • DC output current

    85 mA

    HalfWave

  • Approximate single-wave DC output voltage

    600 V

    HalfWave

  • Approximate full-wave DC output voltage

    700 V

    FullWave