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Power - Pentode Single (NOT beam) (under 10W) ·Pentode

PM24M

Mullard directly heated output pentode for AC-mains receivers, providing approximately 2.8 W Class A audio output.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4
Base pins
4
Nominal heater
4 V / 1.1 A

Description

The Mullard PM24M is a directly heated output pentode for AC mains receivers, with about 2.8 W published Class A output.

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
4
Nominal heater voltage
4 V
Nominal heater current
1.1 A
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
43000 Ω
Transconductance
0.003 S
Max plate voltage
250 V
Max screen voltage
250 V
Max plate dissipation
7.5 W
Max screen dissipation
2 W

Directly heated audio output pentode.

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 Mullard Receiving Tubes

Published operating points and test conditions from this source.

SECTION 1

Pentode

Other

  • Plate Voltage

    250 V

    ClassA

  • Screen Voltage

    250 V

    ClassA

  • Plate Current

    30 mA

    ClassA

  • Screen Current

    5.6 mA

    ClassA

  • Power Output

    2.8 W

    ClassA

  • Load Resistance

    7000 ohm

    ClassA