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

TD2500A

Forced-air-cooled Mullard ceramic disc-seal power triode for RF oscillator, amplifier, and frequency-multiplier service. Rated around 500 W dissipation and 2.7 kV, it provides substantial high-frequency transmitting power.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
3.4 V / 19 A

Description

The Mullard TD2500A is a forced-air-cooled ceramic disc-seal triode for RF oscillator, amplifier or frequency-multiplier 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
3.4 V
Nominal heater current
19 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
Plate resistance
5000 Ω
Transconductance
0.014 S
Amplification factor
70
Max plate voltage
2700 V
Max plate dissipation
500 W

Forced-air-cooled ceramic disc-seal triode for RF oscillator, amplifier or frequency-multiplier service.

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

1963 Mullard

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater/Filament Voltage

    3.4 V

  • Heater/Filament Current

    19 A

  • Transconductance

    14000 uS

  • Amplification Factor

    70 ratio

  • Plate Resistance

    5000 ohm

  • Plate Voltage

    2000 V

  • Plate Current

    240 mA

  • Grid Voltage

    -2 V

  • Plate-Grid Capacitance

    3.8 pF

  • Grid-Filament Capacitance

    11 pF

  • Plate-Filament Capacitance

    0.05 pF

Other

  • Maximum Plate Voltage

    2700 V

  • Maximum Plate Dissipation

    500 W

  • Maximum Operating Frequency

    1000 MHz

  • RF Output Power

    580 W

    Representative

  • RF Output Power

    620 W

    ClassC; GroundedGrid; 400MHz

  • RF Output Power

    533 W

    ClassC; GroundedGrid; 625MHz