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Tube Tinker — Electron Tube Database
Alternatives & variationsDownload PDF datasheet

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

8990A

No short description is recorded for this tube.

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

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
-
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
10000 V
Max screen voltage
2000 V
Max plate dissipation
20000 W
Max screen dissipation
450 W
Max grid dissipation
200 W

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

1976 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Plate Voltage

    8000 V

    Illustrative plate-modulated RF operation; see mode-specific datasheet

  • Screen Voltage

    1500 V

    Illustrative plate-modulated RF operation; see mode-specific datasheet

  • Grid Voltage

    -500 V

    Illustrative plate-modulated RF operation; see mode-specific datasheet

  • Plate Current

    3500 mA

    Illustrative plate-modulated RF operation; see mode-specific datasheet