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

4CX35000A

Forced-air ceramic power tetrode for roughly 50 kW transmitter output, supporting Class-C and AB RF amplification, oscillation, and push-pull AF amplifier or modulator service to about 110 MHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
10 V / 300 A

Description

The Eimac 4CX35,000A and 4CX35,000C ceramic-metal power tetrodes are intended for use at the fifty kilowatt output power level, The 4CX35,000A is recommended for use as a Class-C r-f amplifier or oscillator, Class-ABy r-f amplifier, or Class-AB] push-pull a-f amplifier or modulator. The 4CX35,000C is a special version with a longer screen-anode insulator intended specifically for use as a plate-and screen-modulated Class=-C r-f amplifier. Both types carry full ratings to 110 megacycles,

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
10 V
Nominal heater current
300 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

Tetrode

X-ray radiationInterelectrode capacitances
Amplification factor
5.5
Max plate voltage
10000 V
Max screen voltage
2500 V
Max plate dissipation
35000 W
Max screen dissipation
1500 W
Max grid dissipation
450 W
Max cathode current
10 A

Single electrical section; values mapped from printed ratings/characteristics.

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

Tetrode

Other

  • for use at the fifty kilowatt output power level, The

    5000 kilowatt

    for use at the fifty kilowatt output power level, The 4CX35,000A is recommended

  • Class-AB] push-pull a-f amplifier or modulator. The

    5000 a

    Class-AB] push-pull a-f amplifier or modulator. The 4CX35,000C is a special version

  • Voltage

    10 Volts

    Voltage - - - - - - 10.0 Volts

  • Current

    300 Amperes

    Current - - - - - - 300 Amperes

  • Feedback

    2.3 uuf

    Feedback - - - 2,3 2.3 uuf

  • Frequency for Maximum Ratings

    110 Megacycles

    Frequency for Maximum Ratings - - - - 110 Megacycles

  • Maximum Seal Temperature

    250 °C

    Maximum Seal Temperature - - - 250°C

  • Maximum Anode Core Temperature

    250 °C

    Maximum Anode Core Temperature - - - - 250°C

  • D-C PLATE VOLTAGE

    10000 VOLTS

    D-C PLATE VOLTAGE - - - - - 10,000 VOLTS

  • D-C SCREEN VOLTAGE

    2500 VOLTS

    D-C SCREEN VOLTAGE - - - - - 2500 VOLTS

  • D-C PLATE CURRENT

    10 AMPERES

    D-C PLATE CURRENT - - - - - 10.0 AMPERES

  • PLATE DISSIPATION

    35000 WATTS

    PLATE DISSIPATION - - - - - 35,000 WATTS

  • SCREEN DISSIPATION

    1500 WATTS

    SCREEN DISSIPATION - - - - - 1500 WATTS

  • GRID DISSIPATION

    450 WATTS

    GRID DISSIPATION - - - - - 450 WATTS

  • D-C Plate Voltage

    10000 Volts

    D-C Plate Voltage - - - - - 10,000 Volts

  • D-C Screen Voltage

    750 Volts

    D-C Screen Voltage - - - - - 750 Volts

  • D-C Grid Voltage

    425 Volts

    D-C Grid Voltage - - - - - -425 Volts

  • D-C Plate Current

    6.8 Amperes

    D-C Plate Current - - - - - 6.80 Amperes

  • D-C Screen Current

    925 Ma

    D-C Screen Current - - - - - 925 Ma

  • D-C Grid Current

    320 Ma

    D-C Grid Current - - - - - 320 Ma

  • Peak R-F Grid Voltage

    575 Volts

    Peak R-F Grid Voltage - - - - - 575 Volts

  • Driving Power

    185 Watts

    Driving Power - - - - - 185 Watts

  • Plate Dissipation

    11700 Watts

    Plate Dissipation - - - - - 11,700 Watts

  • Plate Output Power

    56500 Watts

    Plate Output Power - - - - - 56,500 Watts

  • D-C PLATE VOLTAGE

    10000 VOLTS

    D-C PLATE VOLTAGE - - - . 10,000 VOLTS

  • D-C SCREEN VOLTAGE

    1250 VOLTS

    D-C SCREEN VOLTAGE - - - - - 1250 VOLTS

  • D-C PLATE CURRENT

    10 AMPERES

    D-C PLATE CURRENT - - - - - 10.0 AMPERES

  • PLATE DISSIPATION

    23500 WATTS

    PLATE DISSIPATION - - - - - 23,500 WATTS

  • SCREEN DISSIPATION

    1500 WATTS

    SCREEN DISSIPATION - - - - - 1500 WATTS

  • GRID DISSIPATION

    450 WATTS

    GRID DISSIPATION - - - - - 450 WATTS

  • D-C Plate Voltage

    10000 Volts

    D-C Plate Voltage - - - - - 10,000 Volts

  • D-C Screen Voltage

    750 Volts

    D-C Screen Voltage - - - - - 750 Volts

  • Peak A-F Screen Voltage (for

    705 A

    Peak A-F Screen Voltage (for 100-percent modulation)* - 705 Volts

  • D-C Grid Voltage

    525 Volts

    D-C Grid Voltage - - - - - -525 Volts

  • D-C Plate Current

    6.7 Amperes

    D-C Plate Current - - - - - 6.70 Amperes

  • D-C Screen Current

    1.05 Amperes

    D-C Screen Current - - - - - 1.05 Amperes

  • D-C Grid Current

    315 Ma

    D-C Grid Current - - - - - 315 Ma

  • Peak R-F Grid Voltage

    680 Volts

    Peak R-F Grid Voltage - - - - - 680 Volts

  • Driving Power

    215 Watts

    Driving Power - - - - - 215 Watts

  • Plate Dissipation (at

    17100 Watts

    Plate Dissipation (at 100% Modulation)* - - - 17,100 Watts

  • Plate Output Power

    55600 Watts

    Plate Output Power - - - - - 55,600 Watts

  • D-C PLATE VOLTAGE

    10000 VOLTS

    D-C PLATE VOLTAGE - - - - - 10,000 VOLTS

  • D-C SCREEN VOLTAGE

    2500 VOLTS

    D-C SCREEN VOLTAGE - - - - - 2500 VOLTS

  • D-C PLATE CURRENT

    10 AMPERES

    D-C PLATE CURRENT - - - - - 10.0 AMPERES

  • PLATE DISSIPATION

    35000 WATTS

    PLATE DISSIPATION - - - - - 35,000 WATTS

  • SCREEN DISSIPATION

    1500 WATTS

    SCREEN DISSIPATION - - - - - 1500 WATTS

  • GRID DISSIPATION

    450 WATTS

    GRID DISSIPATION - - - - - 450 WATTS

  • D-C Plate Voltage

    10000 Volts

    D-C Plate Voltage - - - - - 10,000 Volts

  • D-C Screen Voltage

    1500 Volts

    D-C Screen Voltage - - - - - 1500 Volts

  • D-C Grid Voltage *

    290 Volts

    D-C Grid Voltage * - - - - - -290 Volts

  • Zero-Sig D-C Plate Current

    2 Amperes

    Zero-Sig D-C Plate Current - - - - 2.00 Amperes

  • Max-Sig D-C Plate Current

    8.75 Amperes

    Max-Sig D-C Plate Current - - - - 8.75 Amperes

  • Max-Sig D-C Screen Current

    270 Ma

    Max-Sig D-C Screen Current - - - - 270 Ma

  • Peak R-F Grid Voltage

    265 Volts

    Peak R-F Grid Voltage - - - - - 265 Volts

  • Driving Power

    0 Watts

    Driving Power - - - - - 0 Watts

  • Plate Dissipation

    32500 Watts

    Plate Dissipation - - - - - 32,500 Watts

  • Max-Sig Plate Output Power

    55000 Watts

    Max-Sig Plate Output Power .- - - - 55,000 Watts

  • Resonant Load Impedance

    590 Ohms

    Resonant Load Impedance - - - - - 590 Ohms

  • D-C PLATE VOLTAGE

    10000 VOLTS

    D-C PLATE VOLTAGE - - - - - 10,000 VOLTS

  • D-C SCREEN VOLTAGE

    2500 VOLTS

    D-C SCREEN VOLTAGE - - - - - 2500 VOLTS

  • D-C PLATE CURRENT

    10 AMPERES

    D-C PLATE CURRENT - - - - - 10.0 AMPERES

  • PLATE DISSIPATION

    35000 WATTS

    PLATE DISSIPATION - - - - - 35,000 WATTS

  • SCREEN DISSIPATION

    1500 WATTS

    SCREEN DISSIPATION - - - - - 1500 WATTS

  • GRID DISSIPATION

    450 WATTS

    GRID DISSIPATION - - - - - 450 WATTS

  • D-C Plate Voltage - - - Co

    10000 Volts

    D-C Plate Voltage - - - Co- - 10,000 Volts

  • D-C Screen Voltage

    1500 Volts

    D-C Screen Voltage - - - - 1500 Volts

  • D-C Grid Voltage *

    290 Volts

    D-C Grid Voltage * - - - - -290 Volts

  • Zero-Sig D-C Plate Current

    4 Amperes

    Zero-Sig D-C Plate Current - - - 4.00 Amperes

  • Max-Sig D-C Plate Current

    17.5 Amperes

    Max-Sig D-C Plate Current - - - - 17.5 Amperes

  • Max-Sig D-C Screen Current

    540 Ma

    . Max-Sig D-C Screen Current - - - - 540 Ma

  • Peak A-F Driving Voltage (Per Tube)

    265 A

    Peak A-F Driving Voltage (Per Tube) - - - 265 Volts

  • Driving Power

    0 Watts

    Driving Power - - - - - 0 Watts

  • Load Resistance, Plate-to-Plate

    1180 Ohms

    Load Resistance, Plate-to-Plate - - 1180 Ohms

  • Plate Dissipation (Per Tube)

    32500 Watts

    Plate Dissipation (Per Tube) - - - 32,500 Watts

  • Max-Sig Plate OQutput Power

    110000 Watts

    Max-Sig Plate OQutput Power - - - 110,000 Watts

  • and the

    250 °C

    and the 4CX35,000C is 250°C, Sufficient forced-air cooling must be provided to

  • seals below

    250 °C

    seals below 250°C. Tube life is usually prolonged if these areas are maintained

  • maintain anode-core and seal temperatures below

    225 °C

    maintain anode-core and seal temperatures below 225°C with an inlet-air temper-

  • ature of

    30 °C

    ature of 50°C are tabulated below for operation below 30 Mc. These data are for

  • *% Since the power dissipated by the filament represents about

    3000 watts

    *% Since the power dissipated by the filament represents about 3000 watts and since

  • watts, allowance has been made in preparing this tabulation for an additional

    5000 watts

    watts, allowance has been made in preparing this tabulation for an additional 5000

Data set 02

1965 Eimac Tube Manual

Published operating points and test conditions from this source.

SECTION 1

Tetrode

Characteristic

  • Heater/Filament Voltage

    10 V

  • Heater/Filament Current

    300 A

  • Amplification Factor

    5.5

Other

  • Maximum DC Plate Voltage

    10000 V

  • Maximum DC Screen Voltage

    2500 V

  • Maximum Plate/Cathode Current

    10 A

  • Maximum Plate Dissipation

    35000 W

  • Maximum Screen Dissipation

    1500 W

  • Maximum Grid Dissipation

    450 W

  • Frequency for Maximum Ratings

    110 MHz

  • Typical Plate Output Power

    56.5 W

Construction

  • Cooling

    Forced air