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

8240

Eimac low-mu water-cooled power triode for high-power audio amplifier and modulator service. Approximately 5 kW plate dissipation and 6 kV capability provide substantial continuous audio-frequency power for large transmitter modulators.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
7.5 V / 51.5 A

Description

The EIMAC 8240 is a low-mu water-cooled power triode for audio amplifier or 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
51.5 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

Triode

X-ray radiationInterelectrode capacitances
Transconductance
0.011 S
Amplification factor
5.6
Max plate voltage
6000 V
Max plate dissipation
5000 W
Max grid dissipation
50 W
Max cathode current
2.5 A

Promoted from printed general-characteristics and maximum-ratings blocks.

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

1962 Eimac

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Amplification factor

    5.6

  • Transconductance

    11000 uS

Other

  • Maximum DC plate voltage

    6000 V

  • Maximum plate dissipation

    5000 W

  • Representative maximum-signal plate current

    3 A

Data set 02

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

    51.5 A

  • Amplification factor

    5

  • Transconductance

    11000 uS

Capacitance

  • Input/grid-cathode capacitance

    29 pF

  • Output/plate-cathode capacitance

    2.5 pF

  • Feedback/grid-plate capacitance

    17 pF

Other

  • Maximum plate voltage

    6000 V

  • Maximum plate dissipation

    5000 W

  • Maximum grid dissipation

    50 W

  • Maximum plate/cathode current

    2.5 A

  • Frequency for maximum ratings

    75 MHz

  • Typical two-tube audio plate voltage

    6000 V

    ClassAB1;TwoTubes

  • Maximum-signal two-tube audio output

    10000 W

    ClassAB1;TwoTubes