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Rectifier - Half Wave ·Rectifier

3B28

Rugged xenon-filled high-voltage half-wave rectifier for military and industrial supplies over a wide temperature range. Gas-assisted conduction provides substantial current with reliable severe-environment operation.

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

Description

The 3B28 is a xenon-filled half-wave rectifier for high-voltage circuits, designed for operation over a wide temperature range and rugged military or industrial use.

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
4
Nominal heater voltage
2.5 V
Nominal heater current
5 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
Max cathode current
500 mA
Rectifier peak inverse voltage
10000 V
Rectifier nominal output current
250 mA
Rectifier peak forward current
2 A
Rectifier forward voltage drop
14 V
Rectifier warm-up time
5 s

Published ratings/characteristics promoted where semantically applicable; supplemental values retained in parameter table.

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

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

    10 s

Data set 02

1953 RFT Rundfunk Technik

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Inverse voltage maximum

    10 kV

  • Peak plate current maximum

    1 A

  • Average plate current maximum

    250 mA

Characteristic

  • Warm-up time

    30 s

  • Arc voltage at 0.5 A

    12 V

Data set 03

1956 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristics

  • Gas filling

    Xenon

Other

  • Power-supply frequency maximum

    500 Hz

Data set 04

1958 Amperex Industrial

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

  • Filament heating time

    5 s

  • Tube voltage drop

    10 V

Other

  • Peak inverse anode voltage

    10000 V

  • Peak anode current

    1 A

  • Average anode current

    250 mA

Data set 05

1961 Tung Sol

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Filament Voltage

    2.5 V

  • Filament Current

    5 A

  • MaximumSurgeCathodeCurrent

    20 A

Data set 06

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

  • Filament heating time

    5 s

    HalfWave;Xenon

  • Tube voltage drop

    10 V

    HalfWave;Xenon

Other

  • Peak inverse anode voltage maximum

    10000 V

    HalfWave;Xenon

  • Peak anode current maximum

    1 A

    HalfWave;Xenon

  • Average anode current maximum

    250 mA

    HalfWave;Xenon

Data set 07

1966 Tung Sol Electronic Tubes 3 of 4

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Maximum peak inverse voltage high-voltage service

    10000 V

    HalfWaveRectifier

  • Maximum peak cathode current

    5 A

    HalfWaveRectifier

  • Maximum average cathode current

    250 mA

    HalfWaveRectifier

  • Maximum surge cathode current

    20 A

    HalfWaveRectifier

  • Rectifier maximum peak inverse voltage

    10000 V

    PromotedValue

  • Rectifier nominal output current

    250 mA

    PromotedValue

  • Rectifier peak forward current

    5 A

    PromotedValue

  • Maximum Average Cathode Current O.5

    250 mA

    PublishedTable

Characteristics

  • Average anode voltage drop

    10 V

    HalfWaveRectifier

  • Critical anode voltage

    50 V

    HalfWaveRectifier

  • Rectifier forward voltage drop

    10 V

    PromotedValue

  • Rectifier warmup time

    5 s

    PromotedValue

  • 2.5F 5`B Volts

    5 A

    PublishedTable

Data set 08

1971 English Electric Valve

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Filament voltage

    2.5 V

  • Filament current

    5 A

  • Peak current

    1 A

    10 kV PIV

  • Mean current

    250 mA

    10 kV PIV

  • Peak current

    2 A

    5 kV PIV

  • Mean current

    500 mA

    5 kV PIV

  • Fault current

    20 A

    0.1 s maximum

Data set 09

1971 RCA HB3 Binder 6 of 7

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Heater/filament voltage

    2.5 V

  • Heater/filament current

    5 A

  • Peak inverse voltage

    15000 V

  • Peak anode current

    2 A

  • Average anode current

    250 mA

Construction

  • Gas fill

    Mercury vapor / inert gas rectifier class

Characteristic

  • Forward voltage drop

    15 V

    Conducting

Application

  • Application

    High-current half-wave gas rectifier