Alternatives & variations Download PDF datasheet

Rectifier - Full Wave ·Rectifier-Rectifier

274B

Western Electric directly heated full-wave rectifier, electrically equivalent to historical 274A except socket arrangement. Rated for approximately 1.5 kV peak inverse voltage, 225 mA DC output, and substantial peak current.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: OCTAL
Socket code: IO
Base pins: 8
Nominal heater: 5 V / 2 A

Description

Directly heated full-wave rectifier, electrically equivalent to historical 274A except socket. The supplied Emission Labs sheet was read for filament data, maximum ratings, representative operating points, gm/rp/mu, output conditions, capacitances, and rectifier filter conditions as applicable.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: OCTAL
Socket code: IO
Base pins: 8
Nominal heater voltage: 5 V
Nominal heater current: 2 A
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

OCTAL - 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: 1500 V
Rectifier nominal output current: 225 mA
Rectifier peak forward current: 675 mA

Ratings and characteristics promoted from the supplied Western Electric tabular source.

Section 2

Rectifier

X-ray radiationInterelectrode capacitances

Rectifier peak inverse voltage: 1500 V
Rectifier nominal output current: 225 mA
Rectifier peak forward current: 675 mA

Second physical rectifier section; electrical properties populated from the documented 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

1956 Western Electric Tubes

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristic

HeaterOrFilamentVoltage
5 V
HeaterOrFilamentCurrent
2 A

SECTION 2

Rectifier

Characteristic

HeaterOrFilamentVoltage
5 V
HeaterOrFilamentCurrent
2 A

Data set 02

2026 Emission Labs

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Characteristics

Filament voltage
5 V
Filament current
2 A

Other

Maximum AC input voltage
550 V RMS
CapacitorInputFilter;Above350VAC
Maximum DC output current
150 mA
CapacitorInputFilter;Above350VAC
Maximum first capacitor
4 uF
CapacitorInputFilter;Above350VAC
Maximum AC input voltage
660 V RMS
ChokeInputFilter
Maximum DC output current
200 mA
ChokeInputFilter
Typical DC output voltage
450 V
CapacitorInputFilter;OutputCurrent=140mA

SECTION 2

Rectifier

Characteristics

Filament voltage
5 V
Filament voltage
5 V
Filament current
2 A
Filament current
2 A

Other

Maximum AC input voltage
550 V RMS
CapacitorInputFilter;Above350VAC
Maximum AC input voltage
550 V RMS
CapacitorInputFilter;Above350VAC
Maximum DC output current
150 mA
CapacitorInputFilter;Above350VAC
Maximum DC output current
150 mA
CapacitorInputFilter;Above350VAC
Maximum first capacitor
4 uF
CapacitorInputFilter;Above350VAC
Maximum first capacitor
4 uF
CapacitorInputFilter;Above350VAC
Maximum AC input voltage
660 V RMS
ChokeInputFilter
Maximum AC input voltage
660 V RMS
ChokeInputFilter
Maximum DC output current
200 mA
ChokeInputFilter
Maximum DC output current
200 mA
ChokeInputFilter
Typical DC output voltage
450 V
CapacitorInputFilter;OutputCurrent=140mA
Typical DC output voltage
450 V
CapacitorInputFilter;OutputCurrent=140mA

Data set 03

2026 Western Electric 200s

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

AC Plate Voltage Per Plate
660 V RMS
ChokeInputFilter
DC Output Current
225 mA
ChokeInputFilter
AC Plate Voltage Per Plate
450 V RMS
CapacitorInputFilter
DC Output Current
160 mA
CapacitorInputFilter
PeakTransientPlateCurrentPerPlate
2.5 A
MinimumInputChokeInductance
3 H
ChokeInputFilter
Minimum Plate Supply Impedance Per Plate
100 ohm
CapacitorInputFilter
DC Output Voltage At Filter Input
430 V
ChokeInputFilter
DC Output Voltage At Filter Input
475 V
CapacitorInputFilter
FilterInputCapacitance
4 uF
CapacitorInputFilter

SECTION 2

Rectifier

Other

AC Plate Voltage Per Plate
660 V RMS
ChokeInputFilter
AC Plate Voltage Per Plate
660 V RMS
ChokeInputFilter
AC Plate Voltage Per Plate
660 V RMS
ChokeInputFilter
DC Output Current
225 mA
ChokeInputFilter
DC Output Current
225 mA
ChokeInputFilter
DC Output Current
225 mA
ChokeInputFilter
AC Plate Voltage Per Plate
450 V RMS
CapacitorInputFilter
AC Plate Voltage Per Plate
450 V RMS
CapacitorInputFilter
DC Output Current
160 mA
CapacitorInputFilter
DC Output Current
160 mA
CapacitorInputFilter
PeakTransientPlateCurrentPerPlate
2.5 A
PeakTransientPlateCurrentPerPlate
2.5 A
MinimumInputChokeInductance
3 H
ChokeInputFilter
MinimumInputChokeInductance
3 H
ChokeInputFilter
Minimum Plate Supply Impedance Per Plate
100 ohm
CapacitorInputFilter
Minimum Plate Supply Impedance Per Plate
100 ohm
CapacitorInputFilter
DC Output Voltage At Filter Input
430 V
ChokeInputFilter
DC Output Voltage At Filter Input
430 V
ChokeInputFilter
DC Output Voltage At Filter Input
475 V
CapacitorInputFilter
FilterInputCapacitance
4 uF
CapacitorInputFilter