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

3CX800A7

Compact high-mu forced-air-cooled power triode for VHF linear RF amplification. Published grounded-grid Class AB2 service produces about 750 W output, and the tube can also operate as a high-current pulse modulator.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
E11-81
Socket code
E11
Base pins
11
Nominal heater
13.5 V / 1.5 A

Description

Compact forced-air-cooled high-mu power triode for VHF RF linear amplification.

Socket description

Large-wafer Elevenar 11-pin with ring

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
E11-81
Socket code
E11
Base pins
11
Nominal heater voltage
13.5 V
Nominal heater current
1.5 A
Parallel heater voltage
-
Parallel heater current
-
Series capable
No

E11-81 - 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
Amplification factor
200
Max plate voltage
2250 V
Max plate dissipation
800 W
Max grid dissipation
4 W
Max cathode current
600 mA

Maximum ratings promoted from the printed service-rating tables; typical operating values are preserved as parameters.

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

Other

  • Maximum plate voltage

    2250 V

  • Maximum plate/cathode current

    600 mA

  • Maximum plate dissipation

    800 W

  • Maximum grid dissipation

    4 W

Data set 02

199X Svetlana

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Heater Voltage (AC or DC) 13.5 ±

    0.6 V

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

  • Heater Current @

    13.5 V

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

  • CCS

    350 MHz

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

  • ICAS

    450 MHz

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

  • Input

    26 pF

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

  • Output

    6.1 pF

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

  • Plate-Cathode

    0.05 pF

    The Svetlana 3CX800A7 may also be operated as a pulse modulator operating at maxi-

Other

  • Maximum-signal DC plate current

    600 mA

    Maximum ratings Dimensional Data

  • Plate Dissipation

    800 W

    Maximum ratings Dimensional Data

  • Grid Dissipation

    4 W

    Maximum ratings Dimensional Data

  • DC grid current

    60 mA

    Maximum ratings Dimensional Data

  • Zero signal plate current

    15 mA

    Typical Operation, Class AB2, Grounded Grid CW SSB

  • DC grid current 36

    16 mA

    Typical Operation, Class AB2, Grounded Grid CW SSB

  • Cathode input impedance 54

    54 ohms

    Typical Operation, Class AB2, Grounded Grid CW SSB

  • Power output 750

    750 W

    Typical Operation, Class AB2, Grounded Grid CW SSB

  • Resonant load impedance 2700

    2700 Ohms

    Typical Operation, Class AB2, Grounded Grid CW SSB

  • Cooling Air at

    25 ˚C

    Typical Operation, Class AB2, Grounded Grid CW SSB

  • Note: When cooling air inlet temperature is raised to

    50 ˚C

    Typical Operation, Class AB2, Grounded Grid CW SSB