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Power - Triode (over 1000V 100W) ·Triode

3X2500A3

Forced-air-cooled external-anode transmitting triode for amplifier, oscillator, and modulator service. Published conditions provide about 10 kW Class C RF output or roughly 13 kW Class B audio output from two tubes.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
7.5 V / 53 A

Description

The EIMAC 3X2500A3 is a forced-air-cooled external-anode medium-mu transmitting triode 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
7.5 V
Nominal heater current
53 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

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.02 S
Amplification factor
20
Max plate voltage
6000 V
Max plate dissipation
2500 W
Max grid dissipation
150 W
Max cathode current
2.5 A

Highest applicable published rating promoted; service-specific CW, RF, audio, industrial, and pulse limits 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 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Heater/filament voltage

    7.5 V

  • Heater/filament current

    53 A

  • Amplification factor

    20

  • Transconductance

    20000 uS

Capacitance

  • Input/grid-cathode capacitance

    35 pF

  • Output/plate-cathode capacitance

    0.9 pF

  • Feedback/grid-plate capacitance

    20 pF

Other

  • Maximum plate voltage

    6000 V

  • Maximum plate dissipation

    2500 W

  • Maximum grid dissipation

    150 W

  • Maximum plate/cathode current

    2.5 A

  • Frequency for maximum ratings

    75 MHz

  • Typical RF plate voltage

    6000 V

    ClassC

  • Typical RF output power

    10000 W

    ClassC

  • Typical AF two-tube output

    13000 W

    ClassB;TwoTubes