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Power - Tetrode (NOT beam) ·Tetrode

KT63

Output power tetrode designed for receiver audio stages, providing efficient Class-A or Class-AB power amplification from typical receiving-equipment supply voltages.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
IO
Base pins
8
Nominal heater
6.3 V / 700 mA

Description

Output tetrode for AC receivers where medium audio power and high efficiency are required.

Socket description

International Octal

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
IO
Base pins
8
Nominal heater voltage
6.3 V
Nominal heater current
700 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

Tetrode

X-ray radiationInterelectrode capacitances
Max plate voltage
250 V

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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Grid-Anode Capacitance

    0.8 pF

  • Grid-Cathode Capacitance

    9.8 pF

  • Anode-Cathode Capacitance

    9 pF

  • Single-Valve Class-A Anode Voltage

    250 V

    ClassA

  • Single-Valve Class-A Screen Voltage

    250 V

    ClassA

  • Single-Valve Class-A Anode Current

    34 mA

    ClassA

  • Single-Valve Class-A Screen Current

    5.5 mA

    ClassA

  • Single-Valve Class-A Output Power

    3 W

    ClassA

  • Optimum Load

    7000 ohm

    ClassA

  • Push-Pull Class-AB1 Output Power

    6 W

    ClassAB;PushPull;TwoTubes

  • Triode-Connected Transconductance

    0.0024 A/V

  • Triode-Connected Plate Resistance

    3200 ohm