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Power - Triode ·Triode

845

Classic directly heated low-mu power triode for Class A and Class AB audio power or modulator service. Low plate resistance, roughly 100 W plate dissipation, and kilovolt capability support substantial high-quality audio output.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
UX4
Base pins
4
Nominal heater
10 V / 3.25 A

Description

Directly heated transmitting triode for Class-A/Class-AB modulator and audio power service.

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
10 V
Nominal heater current
3.25 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
2100 Ω
Transconductance
0.003 S
Amplification factor
5
Max plate voltage
1250 V
Max plate dissipation
100 W
Max cathode current
96 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

  • HeaterVoltageNominal

    10 V

    Nominal

  • HeaterCurrentNominal

    3.25 A

    Nominal

  • Maximum Plate Voltage

    1250 V

  • Maximum Plate Dissipation

    75 W

  • UndistortedPowerOutput

    24 W

    ClassA; 1250 V plate

Characteristic

  • Transconductance

    2500 µS

    Typical

  • Amplification Factor

    5.3

    Typical

Data set 02

193X Taylor Transmitting

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Filament Voltage

    10 V

    Nominal published value

  • Filament Current

    3.85 A

    Nominal published value

  • Maximum Operating Plate Voltage

    1250 V

    Class C oscillator / RF power-amplifier service where published

  • Maximum Plate Dissipation

    75 W

    Published maximum rating

  • class

    14 pF

    Published direct interelectrode capacitance

  • Plate to Filament

    6 pF

    Published direct interelectrode capacitance

Characteristics

  • Plate Resistance

    2100 ohm

    Published general characteristic

  • Mutual Conductance

    3000 µS

    Published general characteristic

  • Amplification Factor

    5

    Published general characteristic

Data set 03

1940 Taylor Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Plate-to-grid capacitance

    14 pF

  • Grid-to-filament capacitance

    6.5 pF

  • Plate-to-filament capacitance

    6 pF

Other

  • Audio output

    21 W

    ClassA PlateVoltage=1000V

  • Audio output

    24 W

    ClassA PlateVoltage=1250V

  • Class AB audio output

    75 W

    ClassAB

  • Class AB audio output

    105 W

    ClassAB

Data set 04

1945 United Electronics

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristics

  • Filament voltage

    10 V

  • Filament current

    3.25 A

Other

  • Maximum direct plate voltage

    1250 V

  • Maximum plate dissipation

    100 W

  • Maximum direct plate current

    96 mA

Data set 05

1953 Amperex

Published operating points and test conditions from this source.

SECTION 1

Triode

Capacitance

  • Grid To Plate Capacitance

    11.5 pF

    Published direct interelectrode capacitance

  • Grid To Filament Capacitance

    5 pF

    Published direct interelectrode capacitance

Data set 06

1956 RCA Transmitting Tubes

Published operating points and test conditions from this source.

SECTION 1

Triode

Characteristic

  • HeaterOrFilamentVoltage

    10 V

  • HeaterOrFilamentCurrent

    3.25 A

Data set 07

1958 Amperex Industrial

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    1250 V

    AudioAmplifier

  • Plate current

    220 mA

    AudioAmplifier

  • Power output

    105 W

    AudioAmplifier

  • Control-grid voltage

    -105 V

    AudioAmplifier

  • Grid current

    30 mA

    AudioAmplifier

  • Maximum frequency at full input

    15 MHz

    Section1

Capacitance

  • Grid-to-plate capacitance

    11.5 pF

    Section1

  • Grid-to-filament capacitance

    5 pF

    Section1

  • Plate-to-filament capacitance

    3.5 pF

    Section1

Data set 08

1963 Amperex Condensed

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • Plate voltage

    1250 V

    RFPowerAmplifier

  • Plate current

    200 mA

    RFPowerAmplifier

  • Power output

    105 W

    RFPowerAmplifier

  • Control-grid voltage

    -225 V

    RFPowerAmplifier

  • Grid current

    0 mA

    RFPowerAmplifier

  • Maximum frequency at full input

    15 MHz

    RFPowerAmplifier

Capacitance

  • Grid-to-plate capacitance

    13.5 pF

    Section1

  • Grid-to-filament capacitance

    6 pF

    Section1

  • Plate-to-filament capacitance

    6.5 pF

    Section1