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Power - Triode ·Triode

4043A

Directly heated power triode for Class B audio or modulator service and RF operation. Its low plate resistance, 35 W plate dissipation, and 600 V plate capability support substantial power stages; later C/D versions improved grid behavior.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B4
Base pins
4
Nominal heater
7.5 V / 1.2 A

Description

Directly heated triode for Class B audio/modulator and RF service. This earlier version is marked for replacement purposes and is replaced by 4043-C/-D.

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
7.5 V
Nominal heater current
1.2 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

Triode

X-ray radiationInterelectrode capacitances
Plate resistance
3500 Ω
Amplification factor
8
Max plate voltage
600 V
Max plate dissipation
35 W
Max cathode current
110 mA

Published ratings/characteristics promoted; remaining useful source values represented 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

1937 Standard Valves

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Grid-anode capacitance

    13.3 pF

  • Anode-filament capacitance

    4.8 pF

  • Grid-filament capacitance

    7 pF

Other

  • Maximum direct anode current

    110 mA

  • Maximum direct grid current

    30 mA

  • Maximum frequency at full ratings

    2 MHz

  • Maximum anode voltage at 10 MHz

    500 V

    Frequency=10MHz

  • Direct anode voltage

    600 V

    ClassB;AF;TwoTubes

  • Load resistance anode-to-anode

    6000 ohm

    ClassB;AF;TwoTubes

  • Maximum output

    60 W

    ClassB;AF;TwoTubes

Data set 02

1946 Standard Telephone and Cables

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater/filament voltage

    7.5 V

  • Heater/filament current

    1.2 A

  • Plate resistance

    3500 ohm

  • Amplification factor

    8

Other

  • Maximum direct anode voltage

    600 V

  • Maximum anode dissipation

    35 W

  • Maximum cathode/anode current

    110 mA