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Power - Triode ·Triode

LS6A

Early Marconi directly heated low-mu audio power triode intended to drive multiple loudspeakers. Rated for about 23 W plate dissipation and 400 V, it provides substantially greater output capability than ordinary receiving triodes.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
B5
Base pins
-
Nominal heater
6 V / 2 A

Description

High-power output valve providing enough output for several speakers, with filament supply options described by the source.

Socket description

European 5-pin base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
B5
Base pins
-
Nominal heater voltage
6 V
Nominal heater current
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
1300 Ω
Transconductance
0.0023 S
Amplification factor
3
Max plate voltage
400 V
Max plate dissipation
23 W
Max cathode current
63 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

192X Marconi Valve

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Published operating data

    See source

    Operating curves/table are present on the approved one-page source; values not promoted unless unambiguous in searchable text.

Data set 02

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Filament Current

    2 A

  • Anode Current Maximum

    63 mA

  • Anode Voltage Maximum

    400 V

  • Anode Dissipation Maximum

    23 W