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Power - Beam (NOT sweep) ·BeamPower

KT55

Indirectly heated beam tetrode designed for audio-output service and also suitable for series-stabilizer voltage-regulator applications.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
IO
Base pins
8
Nominal heater
30 V / 300 mA

Description

Indirectly heated beam tetrode for audio-output service or series-stabilizer use.

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
30 V
Nominal heater current
300 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

Beam Power

X-ray radiationInterelectrode capacitances
Plate resistance
5000 Ω
Transconductance
0.019 S
Max plate voltage
300 V
Max screen voltage
300 V
Max plate dissipation
25 W
Max screen dissipation
5 W

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

Beam Power

Other

  • Anode-All Capacitance

    14 pF

  • Grid1-All Capacitance

    34 pF

  • Anode-Grid1 Capacitance

    0.7 pF

  • Typical Tetrode Anode Voltage

    200 V

  • Typical Tetrode Screen Voltage

    150 V

  • Typical Tetrode Anode Current

    125 mA

  • Typical Tetrode Screen Current

    7.5 mA

  • Push-Pull Output Power

    25 W

    TetrodeConnection;PushPull;TwoTubes

  • Push-Pull Output Power

    15 W

    TriodeConnection;PushPull;TwoTubes

  • Bulb Temperature Maximum

    225 C