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Voltage - Triode (single) ·Triode

L77

Miniature indirectly heated triode for Class A amplification and Class C radio-frequency amplifier or oscillator service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
B7G
Socket code
B7G
Base pins
7
Nominal heater
6.3 V / 150 mA

Description

Miniature indirectly heated triode for Class-A amplification and Class-C RF amplifier/oscillator service.

Socket description

Miniature 7-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
B7G
Socket code
B7G
Base pins
7
Nominal heater voltage
6.3 V
Nominal heater current
150 mA
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

B7G - 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7700 Ω
Transconductance
0.0022 S
Amplification factor
17
Max plate voltage
300 V
Max plate dissipation
3.5 W
Max cathode current
25 mA

Promoted values mapped from printed rating/approximate-data tables; additional operating points and capacitances 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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Grid-Cathode Capacitance

    1.7 pF

  • Anode-Cathode Capacitance

    2.6 pF

  • Grid-Anode Capacitance

    2 pF

  • Class-C Anode Voltage

    300 V

  • Class-C Grid Voltage

    -27 V

  • Class-C Anode Current

    25 mA

  • Class-C Grid Drive

    0.35 W

  • Class-C Output Power

    5.5 W