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

8438

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
5 V / 14.5 A

Description

The EIMAC 8438/4-400A is a compact rugged power tetrode rated at 400 W plate dissipation for amplifier, oscillator and modulator 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
5 V
Nominal heater current
14.5 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
0.004 S
Amplification factor
5.1
Max plate voltage
4000 V
Max screen voltage
750 V
Max plate dissipation
400 W
Max screen dissipation
35 W
Max grid dissipation
10 W
Max cathode current
350 mA

Alias record duplicated from the same published 4400A source.

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

1965 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Other

  • Grid-Plate Capacitance

    0.12 pF

  • Input Capacitance

    12.5 pF

  • Output Capacitance

    4.7 pF

  • Frequency Maximum

    110 MHz

  • Typical Plate Output Power

    630 W

  • Plate-Modulated Plate Voltage Maximum

    3200 V

  • AF Plate Voltage Maximum

    4000 V