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Power - Triode ·Triode

P27500

Tungsram oxide-filament audio power triode with high transconductance. Rated for about 500 V and 25 W dissipation, its relatively low plate resistance provides strong current drive for substantial output stages.

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

Description

Oxide-filament power triode for audio-frequency power amplification.

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
-
Base pins
-
Nominal heater voltage
4 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
1200 Ω
Transconductance
0.0075 S
Max plate voltage
500 V
Max plate dissipation
25 W

Published ratings and characteristics promoted from the approved source.

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

Triode

Other

  • HeaterVoltageNominal

    4 V

    Nominal

  • HeaterCurrentNominal

    2 A

    Nominal

  • Maximum Plate Voltage

    500 V

  • Maximum Plate Dissipation

    25 W

Characteristic

  • Transconductance

    7500 µS

    Typical

  • Plate Resistance

    1200 ohm

    Typical