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

TCL4

Series-heater Tungsram power pentode for transformerless audio-output equipment.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
P8A
Base pins
8
Nominal heater
35 V / 200 mA

Description

Universal-mains high-slope power pentode intended for output-amplifier service.

Socket description

European 8-pin side-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
P8A
Base pins
8
Nominal heater voltage
35 V
Nominal heater current
200 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

Pentode

X-ray radiationInterelectrode capacitances
Plate resistance
43000 Ω
Transconductance
0.008 S
Max plate voltage
400 V
Max screen voltage
400 V
Max plate dissipation
9 W
Max screen dissipation
1.5 W

Published ratings and characteristics promoted where clearly stated; repeated identical sections compressed where applicable.

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

195X Tunsgram

Published operating points and test conditions from this source.

SECTION 1

Pentode

Characteristics

  • Heater or filament voltage

    35 V

    Published nominal value

  • Heater or filament current

    200 mA

    Published nominal value

  • Transconductance

    8000 µS

    Published operating characteristic

Other

  • Maximum plate dissipation

    9 W

    Published maximum rating