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Power - Tetrode (NOT beam) (over 1000V 100W) ·Tetrode

TH298

Forced-air-cooled ceramic-metal coaxial transmitting tetrode for continuous-wave oscillator, grounded-grid RF, television, and FM service.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.2 V / 50 A

Description

The Thomson-CSF TH298 is a forced-air-cooled ceramic/metal coaxial transmitting tetrode for cw oscillator, grounded-grid rf and television/fm service.

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
6.2 V
Nominal heater current
50 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

Tetrode

X-ray radiationInterelectrode capacitances
Transconductance
0.04 S
Amplification factor
7
Max plate voltage
5000 V
Max screen voltage
800 V
Max plate dissipation
5000 W
Max screen dissipation
60 W
Max grid dissipation
40 W

Promoted from printed general-characteristics and maximum-ratings tables.

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

1972 Thomson CSF

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Amplification factor

    7

  • Transconductance

    40000 uS

Other

  • Maximum anode voltage

    5000 V

  • Maximum screen-grid voltage

    800 V

  • Maximum anode dissipation

    5000 W

  • Maximum screen-grid dissipation

    60 W

  • Maximum grid dissipation

    40 W

  • Maximum operating frequency

    300 MHz

  • Typical frequency

    260 MHz

  • Typical anode voltage

    3200 V

  • Typical screen voltage

    600 V

  • Typical anode current

    1.2 A

  • Typical drive power

    90 W

  • Typical output power

    2000 W

Capacitance

  • Grid-anode/input capacitance

    40 pF

  • Grid-cathode/output capacitance

    11 pF

  • Cathode-anode capacitance

    0.04 pF