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Rectifier - Full Wave ·Rectifier-Rectifier

U78

Half-wave rectifier for electronic power-supply service, with manufacturer documentation defining its voltage, current, and intended operating conditions.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
2
Base
-
Socket code
B7G
Base pins
-
Nominal heater
6.3 V / 600 mA

Description

The Marconi U78 is a miniature indirectly heated bi-phase half-wave rectifier.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B7G
Base pins
-
Nominal heater voltage
6.3 V
Nominal heater current
600 mA
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

2 physical sections, each with unique specifications.

Section 1

Rectifier

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
1250 V
Rectifier nominal output current
70 mA
Rectifier peak forward current
210 mA
Rectifier max heater-cathode voltage
450 V

Section 2

Rectifier

X-ray radiationInterelectrode capacitances
Rectifier peak inverse voltage
1250 V
Rectifier nominal output current
70 mA
Rectifier peak forward current
210 mA
Rectifier max heater-cathode voltage
450 V

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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Rectifier

Other

  • Heater/filament voltage

    6.3 V

  • Heater/filament current

    600 mA

  • Peak inverse voltage

    1250 V

  • Nominal/maximum output current

    70 mA

  • Peak anode current

    210 mA

  • Maximum heater-cathode voltage

    450 V

  • Surge anode current

    700 mA

  • Typical output current

    70 mA

    CapacitorInput

Construction

  • Rectifier topology

    Bi-phase/full-wave