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Voltage - Dual Triode (similar) ·Triode-Triode

B65

6.3-volt-heater version of the Marconi B36, an octal indirectly heated double triode intended for general voltage-amplifier service.

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

Description

The Marconi B65 is a 6.3 v heater version of the b36 octal indirectly heated double triode.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7700 Ω
Transconductance
0.0026 S
Amplification factor
20
Max plate voltage
300 V
Max plate dissipation
2.5 W

Representative section for two equal triode systems.

Section 2

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
7700 Ω
Transconductance
0.0026 S
Amplification factor
20
Max plate voltage
300 V
Max plate dissipation
2.5 W

Second physical triode restored under current one-row-per-physical-section policy.

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

  • Heater voltage

    6.3 V

  • Heater current

    600 mA

  • Maximum plate voltage

    300 V

  • Maximum plate dissipation per section

    2.5 W

Characteristic

  • Amplification factor

    20

  • Transconductance

    2600 uS

  • Plate resistance

    7700 ohm

Capacitance

  • Grid-plate capacitance

    2.5 pF

  • Grid-cathode capacitance

    2.6 pF

  • Plate-cathode capacitance

    0.3 pF