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

8621

High-power transmitting tetrode designed for RF power amplification, linear amplification, oscillation, modulation, or frequency multiplication.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
26.5 V / 540 mA

Description

8621/4CX250FG 26.5-V-heater companion to 7203/4CX250B.

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
26.5 V
Nominal heater current
540 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
Amplification factor
5
Max plate voltage
2000 V
Max screen voltage
400 V
Max plate dissipation
250 W
Max screen dissipation
12 W
Max grid dissipation
2 W

Promoted fields populated from published ratings/characteristics; additional published values retained in TUBE_SECTION_PARAMETER.

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

Tetrode

Capacitance

  • Input Capacitance

    15.7 pF

  • Output Capacitance

    4.5 pF

  • Grounded Cathode Feedback Capacitance

    0.04 pF

  • Grounded Grid Feedback Capacitance

    0.01 pF

Other

  • Frequency of Maximum Rating CW

    500 MHz

  • Maximum DC Plate Current

    250 mA

  • Typical Linear Plate Voltage

    2000 V

    ClassAB1

  • Typical Linear Plate Output Power

    300 W

    ClassAB1