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Rectifier - Full Wave ·Rectifier-Rectifier

274A

Historical Western Electric directly heated full-wave rectifier, electrically equivalent to 274B except for socket arrangement. Its 5 V filament supports approximately 1.65 kV peak inverse voltage and 150 mA DC output.

Directly heatedCold cathodeCommon cathodeDissimilar

Sections: 2
Base: UX4
Socket code: MEDIUM4BAYONET
Base pins: 4
Nominal heater: 5 V / 2 A

Description

Historical 274A designation explicitly stated electrically equivalent to 274B 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

Medium 4-contact bayonet base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base: UX4
Socket code: MEDIUM4BAYONET
Base pins: 4
Nominal heater voltage: 5 V
Nominal heater current: 2 A
Parallel heater voltage: -
Parallel heater current: -
Series capable: No

UX4 - 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: 1650 V
Rectifier nominal output current: 150 mA

Filter-specific ratings preserved in parameters.

Section 2

Rectifier

X-ray radiationInterelectrode capacitances

Rectifier peak inverse voltage: 1650 V
Rectifier nominal output current: 150 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 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

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
150 mA
ChokeInputFilter
AC Plate Voltage Per Plate
450 V RMS
CapacitorInputFilter
DC Output Current
130 mA
CapacitorInputFilter

SECTION 2

Rectifier

Other

AC Plate Voltage Per Plate
660 V RMS
ChokeInputFilter
DC Output Current
150 mA
ChokeInputFilter
AC Plate Voltage Per Plate
450 V RMS
CapacitorInputFilter
DC Output Current
130 mA
CapacitorInputFilter