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Power - Triode ·Triode

P240

Super-power output triode for driving moving-coil loudspeakers.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4
Base pins
-
Nominal heater
2 V / 400 mA

Description

Super-power output triode for moving-coil loudspeakers.

Socket description

European 4-pin base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B4
Base pins
-
Nominal heater voltage
2 V
Nominal heater current
400 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
2500 Ω
Transconductance
0.0016 S
Amplification factor
4
Max plate voltage
150 V

Published ratings/characteristics promoted from the approved datasheet where legible.

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

192X Marconi Valve

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Typical anode current at 100 V

    11 mA

    Published approximate operating data

  • Typical anode current at 125 V

    14 mA

    Published approximate operating data

Data set 02

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Filament/heater voltage

    2 V

  • Filament/heater current

    400 mA

  • Maximum anode voltage

    150 V

  • Typical anode voltage

    150 V

  • Typical anode current

    17 mA