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Power - Triode ·Triode

808

Transmitting power triode intended for RF amplifier and oscillator service, with manufacturer ratings emphasizing radio-frequency output, substantial plate loading, and professional transmitter operation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
UX4
Base pins
4
Nominal heater
7.5 V / 4 A

Description

Thoriated-tungsten power triode for RF power-amplifier and oscillator service, usable with full input to about 80 MHz.

Socket description

Medium-shell UX 4-contact

General specifications

Tube and section characteristics

Properties common to every published source and operating point.

Heater and base

Base
-
Socket code
UX4
Base pins
4
Nominal heater voltage
7.5 V
Nominal heater current
4 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
Amplification factor
47
Max plate voltage
1500 V
Max plate dissipation
50 W
Max cathode current
150 mA

Published ratings and characteristics from source sheet.

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

1938 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • operated at maximum ratings at frequencies as high as

    30 MHz

    operated at maximum ratings at frequencies as high as 30 megacycles. The maximum

  • plate dissipation is

    50 W

    plate dissipation is 50 watts for class C telegraph and class B services.

  • D-C Plate Voltage .. 1250

    1500 V

    D-C Plate Voltage .. 1250 1500 Volts

  • Effective Load Res. (Plate-to-plate) ... 12700

    18300 Ω

    Effective Load Res. (Plate-to-plate) ... 12700 18300 Ohms

  • D-C Plate Current

    75 mA

    D-C Plate Current.... ---- 75 max. Milliamperes

  • Plate Input

    75 W

    Plate Input.. 75 Watts

  • Plate Dissipation

    50 W

    Plate Dissipation -- 50 max. Watts

  • D-C Plate Voltage. . 1250

    1500 V

    D-C Plate Voltage. . 1250 1500 Volts

  • Peak R-F Grid Voltage .. . 65

    60 V

    Peak R-F Grid Voltage .. . 65 60 Volts

  • D-C Plate Current... . 55

    45 mA

    D-C Plate Current... . 55 45 Milliamperes

  • D-C Grid Current (Approx.) ... . 1

    1 mA

    D-C Grid Current (Approx.) ... . 1 1 Milliampere

  • D-C Plate Voltage

    1250 V

    D-C Plate Voltage . 1250 max. Volts

  • D-C Grid Voltage

    -400 V

    D-C Grid Voltage . -400 max. Volts

  • D-C Plate Current

    125 mA

    D-C Plate Current. 125 max. Milliamperes

  • D-C Grid Current

    35 mA

    D-C Grid Current . .... 35 max. Milliamperes

  • Plate Dissipation

    35 W

    Plate Dissipation . 35 max. Watts

  • D-C Plate Voltage . 1000

    1250 V

    D-C Plate Voltage . 1000 1250 Volts

  • Peak R-F Grid Voltage . 360

    360 V

    Peak R-F Grid Voltage . 360 360 Volts

  • D-C Plate Current . 120

    100 mA

    D-C Plate Current . 120 100 Milliamperes

  • D-C Grid Current (Approx.) .. 35

    32 mA

    D-C Grid Current (Approx.) .. 35 32 Milliamperes

  • Driving Power (Approx.) . 11.5

    10.5 W

    Driving Power (Approx.) . 11.5 10.5 Watts

  • Power Output (Approx.) . 85

    105 W

    Power Output (Approx.) . 85 105 Watts

  • D-C Plato Voltage

    1500 V

    D-C Plato Voltage .... 1500 max. Volts

  • D-C Grid Voltage

    -400 V

    D-C Grid Voltage.... -400 max. Volts

  • D-C Plate Current

    150 mA

    D-C Plate Current... 150 max. Milliamperes

  • D-C Grid Current

    35 mA

    D-C Grid Current ...... 35 max. Milliamperes

  • Plate Dissipation

    50 W

    Plate Dissipation .. 50 max. Watts

  • D-C Plate Voltage. 1250

    1500 V

    D-C Plate Voltage. 1250 1500 Volts

  • Peak R-F Grid Voltage. 300

    350 V

    Peak R-F Grid Voltage. 300 350 Volts

  • D-C Plate Current . 135

    125 mA

    D-C Plate Current . 135 125 Milliamperes

  • D-C Grid Current (Approx.) .. 30

    30 mA

    D-C Grid Current (Approx.) .. 30 30 Milliamperes

  • Grid Resistor . 5000

    6670 Ω

    Grid Resistor . 5000 6670 Ohms

  • Driving Power (Approx.) . 8

    9.5 W

    Driving Power (Approx.) . 8 9.5 Watts

  • Power Output (Approx.) . 120

    140 W

    Power Output (Approx.) . 120 140 Watts

  • each stated value of grid voltage should be decreased by

    5 V

    each stated value of grid voltage should be decreased by 5 volts and ttie circuit returns made to the

  • when the 808 is operated at a plate voltage of

    1000 V

    when the 808 is operated at a plate voltage of 1000 volts or less. If the grid

  • For high-frequency operation above

    30 MHz

    For high-frequency operation above 30 megacycles, see page 144.

Data set 02

1956 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • Amplification Factor

    47

Other

  • Maximum Plate Voltage

    2000 V

  • Maximum Plate Dissipation

    75 W

  • Maximum Cathode Current

    150 mA

  • Full-Input Operating Frequency Maximum

    80 MHz

  • Power Output

    225 W

    ClassC,RF

  • Typical Plate Voltage

    750 V

    Representative published point

  • Typical Plate Current

    100 mA

    Representative published point