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Rectifier - Half Wave ·Rectifier

872A

Directly heated coated-filament mercury-vapor half-wave rectifier for transmitting and industrial high-voltage supplies. Its low arc voltage provides efficient ampere-class power conversion.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
A4-29
Socket code
UX4
Base pins
4
Nominal heater
5 V / 7.5 A

Description

Coated-filament half-wave mercury-vapor rectifier for high-voltage transmitting and industrial power supplies.

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
A4-29
Socket code
UX4
Base pins
4
Nominal heater voltage
5 V
Nominal heater current
7.5 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

A4-29 - 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
Max cathode current
8 A
Rectifier peak inverse voltage
10000 V
Rectifier nominal output current
1.25 A
Rectifier peak forward current
5 A
Rectifier forward voltage drop
10 V
Rectifier warm-up time
30 s

Promoted values are taken from printed General Characteristics / Maximum Ratings. Additional published conditions and operating data are 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

1938 Raytheon Amateur

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Application

  • Application

    MercuryVaporHalfWaveRectifier text

Data set 02

1938 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • HeaterVoltageNominal

    5 V

    Nominal

  • HeaterCurrentNominal

    6.75 A

    Nominal

  • Maximum Peak Inverse Voltage

    10000 V

  • Rectified Output Current

    1.25 A

  • PeakForwardCurrent

    5 A

Characteristic

  • Forward Voltage Drop

    10 V

Data set 03

1940 Taylor Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Peak inverse voltage

    10000 V

    CondensedMercuryTemperature=20-60C

  • Peak inverse voltage

    5000 V

    CondensedMercuryTemperature=20-70C

  • RMS AC input voltage

    3580 V

    SinglePhaseFullWaveTwoTubes

  • Maximum DC output voltage

    3180 V

    SinglePhaseFullWaveTwoTubes

  • Maximum DC output current

    2.5 A

    SinglePhaseFullWaveTwoTubes

  • RMS AC input voltage

    7060 V

    SinglePhaseBridgeFourTubes

  • Maximum DC output voltage

    6360 V

    SinglePhaseBridgeFourTubes

  • Maximum DC output current

    2.5 A

    SinglePhaseBridgeFourTubes

  • RMS AC input voltage

    4080 V

    ThreePhaseHalfWaveThreeTubes

  • Maximum DC output voltage

    4780 V

    ThreePhaseHalfWaveThreeTubes

  • Maximum DC output current

    3.75 A

    ThreePhaseHalfWaveThreeTubes

  • RMS AC input voltage

    4080 V

    ThreePhaseParallelDoubleYSixTubes

  • Maximum DC output voltage

    4780 V

    ThreePhaseParallelDoubleYSixTubes

  • Maximum DC output current

    7.5 A

    ThreePhaseParallelDoubleYSixTubes

  • RMS AC input voltage

    4080 V

    ThreePhaseFullWaveSixTubes

  • Maximum DC output voltage

    4780 V

    ThreePhaseFullWaveSixTubes

  • Maximum DC output current

    3.75 A

    ThreePhaseFullWaveSixTubes

Data set 04

1945 United Electronics

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Filament voltage

    5 V

    Nominal general rating

  • Filament current

    6.75 A

    Nominal general rating

Data set 05

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Supply frequency

    50 Hz

    ChokeInputFilter

  • Minimum cathode heating time

    1 min

Data set 06

1950 Eimac Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

  • Filament Voltage

    5 V

  • Filament Current

    7.5 A

  • Approximate Tube Voltage Drop

    10 V

  • Recommended Condensed Mercury Temperature

    40 C

    ±5 C

  • Initial Mercury Redistribution Heating Time

    10 min

    No plate voltage

  • Normal Filament Warm-up Before Plate Voltage

    30 s

    Approximate

Other

  • Maximum Peak Inverse Anode Voltage

    10000 V

    At condensed-mercury temperature 20-60 C

  • Maximum Peak Anode Current

    5 A

  • Maximum Average Anode Current

    1.25 A

  • Maximum Supply Frequency

    150 Hz

    At 10 kV PIV

  • Condensed Mercury Temperature Range

    20-60 C

Application

  • Preferred Filter Type

    Choke input

    Greatest usable DC output current

  • Condenser-Input Filter Note

    Peak current relatively high; capacitor voltage may approach 1.4× transformer RMS voltage

Data set 07

1950 General Electric Transmitting Types

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Maximum Cathode Current

    8 A

  • Peak Inverse Voltage

    10000 V

  • Surge Cathode Current

    50 A

    Maximum duration 0.2 second

  • Maximum Frequency

    150 Hz

Characteristic

  • Forward Voltage Drop

    15 V

Data set 08

1953 Amperex

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Heater/Filament Voltage

    5 V

    Published datasheet value

  • Heater/Filament Current

    6.75 A

    Published datasheet value

  • Maximum Peak Inverse Voltage

    10000 V

    Published datasheet value

  • Maximum Average/Output Current

    1.25 A

    Published datasheet value

Data set 09

1956 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

  • HeaterOrFilamentVoltage

    5 V

  • HeaterOrFilamentCurrent

    7.5 A

  • WarmupTimeMinimum

    30 s

    Before anode voltage

Data set 10

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Condensed Mercury Temperature Range

    20 to 60 C

  • Supply Frequency Maximum

    150 Hz

Data set 11

1971 Machlette Laboratories

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Maximum peak inverse anode voltage

    10000 V

  • Maximum average anode current

    1.25 A

Data set 12

1971 RCA HB3 Binder 6 of 7

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Heater/filament voltage

    5 V

  • Heater/filament current

    7.5 A

  • Peak inverse anode voltage

    10000 V

  • Peak anode current

    5 A

  • Average anode current

    1.25 A

  • Fault current

    50 A

    ShortDuration

Characteristic

  • Peak tube voltage drop

    15 V

    Conducting

Construction

  • Gas fill

    Mercury vapor