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Voltage Pentode ·Pentode

77E

Brimar RF pentode with a 6.3 V, 0.3 A heater and high anode impedance. Manufacturer data identify it as a radio-frequency signal-amplifier tube rather than a power-output device.

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

Description

The BRIMAR 77E is an RF pentode with a 6.3 V, 0.3 A heater, 1.5 megohm anode impedance, and 1.2 mA/V mutual conductance.

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
91000 Ω
Transconductance
0.0011 S
Amplification factor
100
Max plate voltage
250 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

1948 Brimar Radio Valve Manual

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Anode Voltage

    250 V

  • Anode Current

    2.3 mA

  • Screen Voltage

    100 V

  • Screen Current

    0.5 mA

  • Control Grid Voltage

    -3 V

  • Cutoff Grid Voltage

    -7.5 V