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Voltage Pentode - Remote Cutoff (single) ·Pentode

78E

Brimar variable-mu RF pentode designed for radio-frequency amplifier service. Its gradual cutoff characteristic provides controlled receiver gain under automatic-volume-control operation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
UX6
Base pins
6
Nominal heater
6.3 V / 300 mA

Description

The BRIMAR 78E is a vari-mu RF pentode intended for radio-frequency amplifier service.

Socket description

Small 6-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
UX6
Base pins
6
Nominal heater voltage
6.3 V
Nominal heater current
300 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

1 physical section, each with unique specifications.

Section 1

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
800000 Ω
Transconductance
0.00145 S
Max plate voltage
250 V
Max screen voltage
100 V

Published Brimar values promoted where applicable; additional data retained as parameters.

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

1958 Brimar Radio Valve No 7

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Cutoff characteristic

    Variable-mu