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

204A

Filamentary power triode intended for transmitting service as an RF amplifier or oscillator, with operating data emphasizing substantial plate input and output power rather than small-signal amplification.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
UX4
Base pins
4
Nominal heater
11 V / 3.85 A

Description

The RCA 204A is a large transmitting power triode. The supplied source provides transmitting, RF, or rectifier ratings appropriate to this device.

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
11 V
Nominal heater current
3.85 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
6300 Ω
Transconductance
0.004 S
Amplification factor
23
Max plate voltage
2500 V
Max plate dissipation
250 W
Max cathode current
275 mA

Maximum ratings and characteristic constants promoted where reliably published in the approved 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

  • megacycles. The maximum plate dissipation is

    250 W

    megacycles. The maximum plate dissipation is 250 watts for class C telegraph

  • D-C Plate Voltage..... 2000 2500

    3000 V

    D-C Plate Voltage..... 2000 2500 3000 Volts

  • Max.-Signal D-C Plate Current - 500 420

    372 mA

    Max.-Signal D-C Plate Current - 500 420 372 Milliamperes

  • Max.-Sig. Driving Power (Approx.) 20 18

    18 W

    Max.-Sig. Driving Power (Approx.) 20 18 18 Watts

  • D-C Plate Voltage

    2500 V

    D-C Plate Voltage 2500 max. Volts

  • D-C Plate Current

    225 mA

    D-C Plate Current 225 max. Milliamperes

  • Plate Input

    400 W

    Plate Input - 400 max. Watts

  • D-C Plate Current- 200

    160 mA

    D-C Plate Current- 200 160 Milliamperes

  • D-C Plate Voltage

    2000 V

    D-C Plate Voltage 2000 max. Volts

  • D-C Grid Voltage

    -500 V

    D-C Grid Voltage . -500 max. Volts

  • D-C Plate Current

    275 mA

    D-C Plate Current 275 max. Milliamperes

  • D-C Grid Current

    80 mA

    D-C Grid Current . 80 max. Milliamperes

  • Plate Input

    550 W

    Plate Input. 550 max. Watts

  • Plate Dissipation

    167 W

    Plate Dissipation . 167 max. Watts

  • D-C Plate Current.. 250

    250 mA

    D-C Plate Current.. 250 250 Milliamperes

  • Grid Resistor .... 5710

    7140 Ω

    Grid Resistor .... 5710 7140 Ohms

  • Power Output (Approx.) ... 225

    350 W

    Power Output (Approx.) ... 225 350 Watts

  • D-C Plate Voltage

    2500 V

    D-C Plate Voltage . 2500 max. Volts

  • D-C Grid Voltage

    -500 V

    D-C Grid Voltage... -500 max. Volts

  • D-C Grid Current

    80 mA

    D-C Grid Current . 80 max. Milliamperes

  • Plate Dissipation

    250 W

    Plate Dissipation . --- .. 250 max. Watts

  • D-C Plate Voltage--- 1500 2000

    2500 V

    D-C Plate Voltage--- 1500 2000 2500 Volts

  • Peak R-F Grid Voltage .-. 400 425

    440 V

    Peak R-F Grid Voltage .-. 400 425 440 Volts

  • D-C Plate Current.. 250 250

    250 mA

    D-C Plate Current.. 250 250 250 Milliamperes

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

    30 mA

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

  • Driving Power (Approx.) . 15 15

    15 W

    Driving Power (Approx.) . 15 15 15 Watts

  • Power Output (Approx.) --- 240 350

    450 W

    Power Output (Approx.) --- 240 350 450 Watts

  • each 6tated value of grid voltage should be decreased by

    8 V

    each 6tated value of grid voltage should be decreased by 8 volts and the circuit returns made to the

  • For high-frequency operation above

    3 MHz

    For high-frequency operation above 3 megacycles, see page 144.

Data set 02

193X Taylor Transmitting

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Filament Voltage

    11 V

    Nominal published value

  • Filament Current

    4 A

    Nominal published value

  • Maximum Operating Plate Voltage

    2500 V

    Class C oscillator / RF power-amplifier service where published

  • Maximum Plate Dissipation

    250 W

    Published maximum rating

  • Plate to Grid

    16 pF

    Published direct interelectrode capacitance

  • Grid to Filament

    14 pF

    Published direct interelectrode capacitance

Characteristics

  • Plate Resistance

    6300 ohm

    Published general characteristic

  • Mutual Conductance

    4000 µS

    Published general characteristic

  • Amplification Factor

    25

    Published general characteristic

Data set 03

1945 United Electronics

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Filament voltage

    11 V

  • Filament current

    3.85 A

  • Plate resistance

    6300 ohm

  • Mutual conductance

    4000 uS

  • Amplification factor

    23

Other

  • Maximum direct plate voltage

    2500 V

  • Maximum plate dissipation

    250 W

  • Maximum direct plate current

    275 mA

Data set 04

1956 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Maximum Plate/Inverse Voltage

    2500 V

    Source rating

  • Maximum Plate Dissipation

    250 W