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Rectifier - Half Wave ·Rectifier

857B

Directly heated high-current mercury-vapor half-wave rectifier for high-power broadcasting stations. Its massive filament and low arc voltage provide multiampere output at high voltage.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4B
Base pins
4
Nominal heater
5 V / 30 A

Description

High-current mercury-vapor half-wave rectifier for high-power broadcasting stations.

Socket description

Medium 4-pin bayonet

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B4B
Base pins
4
Nominal heater voltage
5 V
Nominal heater current
30 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
22000 V
Rectifier nominal output current
10 A
Rectifier peak forward current
40 A
Rectifier forward voltage drop
10 V
Rectifier warm-up time
60 s

Mercury-vapor rectifier maximum inverse-voltage and average-anode-current ratings promoted from the source.

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

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

    30 A

    Published datasheet value

  • Maximum Peak Inverse Voltage

    22000 V

    Published datasheet value

  • Maximum Average/Output Current

    10 A

    Published datasheet value

Data set 02

1958 Amperex Industrial

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Filament voltage

    5 V

    MercuryVapor

  • Filament current

    30 A

    MercuryVapor

  • Peak inverse anode voltage maximum

    22000 V

    HalfWave;MercuryVapor

  • Peak anode current maximum

    40 A

    HalfWave;MercuryVapor

  • Average anode current maximum

    10 A

    HalfWave;MercuryVapor

  • Recommended mercury temperature range

    Mercury +30 to +40 °C

    MercuryVapor

  • Surge current maximum

    400 A

    HalfWave;MercuryVapor

Characteristic

  • Filament heating time

    60 s

    MercuryVapor

  • Tube voltage drop

    10 V

    MercuryVapor

Data set 03

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

  • Filament heating time

    60 s

    HalfWave;MercuryVapor

  • Tube voltage drop

    10 V

    HalfWave;MercuryVapor

Other

  • Peak inverse anode voltage maximum

    22000 V

    HalfWave;MercuryVapor

  • Peak anode current maximum

    40 A

    HalfWave;MercuryVapor

  • Average anode current maximum

    10 A

    HalfWave;MercuryVapor

  • Recommended mercury temperature range

    +30 to +40 °C

    MercuryVapor

  • Surge current maximum

    400 A

    HalfWave;MercuryVapor

Data set 04

1971 English Electric Valve

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • DC Output Voltage

    21 kV

    ThreePhase; FullWave

  • DC Output Current

    30 A

    ThreePhase; FullWave

  • DC Output Voltage

    7 kV

    SinglePhase; FullWave

  • DC Output Current

    20 A

    SinglePhase; FullWave

Data set 05

1971 Machlette Laboratories

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Maximum peak inverse anode voltage

    22000 V

  • Maximum average anode current

    10 A

Data set 06

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

    33 A

  • Peak inverse anode voltage

    22000 V

  • Peak anode current

    40 A

  • Average anode current

    10 A

  • Fault current

    400 A

    ShortDuration

  • X-ray warning threshold

    16000 V

    PeakInverseVoltage

  • Condensed-mercury temperature range

    30 to 40 degC

    22000VPIV

Characteristic

  • Peak tube voltage drop

    25 V

    Conducting

Construction

  • Gas fill

    Mercury vapor