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

PL4D21

Power tetrode with 125-watt plate dissipation designed for RF amplifier, oscillator, and modulator service to approximately 120 MHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
GIANT5
Base pins
5
Nominal heater
-

Description

The Penta PL4D21 is a power tetrode with 125 w plate dissipation for rf amplifier, oscillator, and modulator 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
-
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
Transconductance
0.0025 S
Max plate voltage
4000 V
Max screen voltage
600 V
Max plate dissipation
125 W
Max grid dissipation
5 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

  • Transconductance

    2500 uS

Other

  • Maximum plate voltage

    4000 V

  • Maximum screen voltage

    600 V

  • Maximum plate dissipation

    125 W

  • Maximum control-grid dissipation

    5 W

  • Source language

    English

  • Maximum frequency for full ratings

    120 MHz

Application

  • Primary application

    Power tetrode with 125 W plate dissipation for RF amplifier, oscillator, and modulator service.

Construction

  • Cooling

    Radiation/convection or source-specific

  • Electrode structure

    Tetrode