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Power - Beam (NOT sweep) (over 1000V 100W) ·BeamPower

8990

Very-high-power forced-air radial-beam tetrode for audio, FM, linear RF, and television transmitting service, rated around 20 kW plate dissipation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
10 V / 140 A

Description

The EIMAC 8990 is a forced-air-cooled ceramic/metal radial-beam power tetrode for audio, fm, linear rf and television 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
10 V
Nominal heater current
140 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

Beam Power

X-ray radiationInterelectrode capacitances
Amplification factor
4.5
Max plate voltage
10000 V
Max screen voltage
2000 V
Max plate dissipation
20000 W
Max screen dissipation
450 W
Max grid dissipation
200 W
Max cathode current
5 A

Promoted from printed general-characteristics and absolute-maximum-ratings blocks.

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

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Characteristic

  • Amplification factor

    4.5

Other

  • Maximum DC plate voltage

    10000 V

  • Maximum DC screen voltage

    2000 V

  • Maximum plate dissipation

    20000 W

  • Maximum screen dissipation

    450 W

  • Maximum grid dissipation

    200 W

  • Maximum cathode/plate current

    5 A

Data set 02

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Beam Power

Other

  • HeaterVoltageNominal

    10 V

    Nominal

  • HeaterCurrentNominal

    140 A

    Nominal

  • Maximum Plate Voltage

    10000 V

  • Maximum Screen Voltage

    2000 V

  • Maximum Plate Dissipation

    20000 W

  • Maximum Screen Dissipation

    450 W