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

PL8438

Transmitting power tetrode designed for RF amplification, linear/SSB service, oscillation, modulation, broadcasting, or frequency multiplication.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
GIANT5
Base pins
5
Nominal heater
5 V / 14.5 A

Description

The Penta PL8438 is a 400 w power tetrode for rf amplifier, oscillator, modulator, and fm service.

Socket description

Giant 5-contact base

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
GIANT5
Base pins
5
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
800 V
Max plate dissipation
400 W
Max grid dissipation
10 W

Highest reliable published rating promoted; additional values and operating/application details retained as parameter rows.

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 Penta Labs Power Tubes

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Heater/filament voltage

    5 V

  • Heater/filament current

    14.5 A

  • Amplification factor

    5.1

  • Transconductance

    4000 uS

Other

  • Maximum plate voltage

    4000 V

  • Maximum screen voltage

    800 V

  • Maximum plate dissipation

    400 W

  • Maximum control-grid dissipation

    10 W

  • Source language

    English

  • Maximum frequency for full ratings

    110 MHz

  • FM service plate voltage

    3000 V

Capacitance

  • Grid-plate capacitance

    0.12 pF

  • Input capacitance

    12.5 pF

  • Output capacitance

    4.5 pF

Application

  • Primary application

    400 W power tetrode for RF amplifier, oscillator, modulator, and FM service.

Construction

  • Cooling

    Forced air

  • Electrode structure

    Tetrode