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

379A

Machlett air-cooled thoriated-tungsten transmitting triode for modulator, amplifier, and oscillator service. Its approximately 750 W plate dissipation and 2.5 kV plate rating support substantial RF output and high-power audio modulation.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
10 V / 21 A

Description

The ML-279A and ML-379A are three-clectrode tubes de- The ML-279A and ML-379A embody all the techniques and signed for use as modulators, amplifiers, or oscillators in ra- skills that have been inherently a part of Machlett Laborator- dio-transmitting scrvice. The cathode for cach type is a thor- ics, Inc., since 1897, All parts are thoroughly processed by iated-tungsten filament. Each tube is air cooled and its anode special Machlett techniques, which prevent contamination and and 800 milliamperes apply at frequencies up to 20 Mc; oper- hausted by 2 straight-line, high-voltage process assuring the ation at 40 Mc is permissible with plate voltage reduced to same high standards as characterize the Machlett line of high.

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
21 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
Transconductance
0.005 S
Amplification factor
10
Max plate voltage
2500 V
Max plate dissipation
750 W

Promoted fields populated from explicitly published ratings/characteristics; service-specific data retained 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

1971 Machlette Laboratories

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • and [1]

    800 A

    and 800 milliamperes apply at frequencies up to 20 Mc; oper- hausted by 2 straight-line, high-voltage process assuring the

  • and [2]

    20 A

    and 800 milliamperes apply at frequencies up to 20 Mc; oper- hausted by 2 straight-line, high-voltage process assuring the

  • and [3]

    2 A

    and 800 milliamperes apply at frequencies up to 20 Mc; oper- hausted by 2 straight-line, high-voltage process assuring the

  • ation at

    40 mA

    ation at 40 Mc is permissible with plate voltage reduced to same high standards as characterize the Machlett line of high.

  • Published value

    1.5

    1.5 kVdec. and super-voltage x-ray tubes.

  • Filament Current at [1]

    10 V

    Filament Current at 10 Volts 21.0 ampceres

  • Filament Current at [2]

    21 V

    Filament Current at 10 Volts 21.0 ampceres

  • Amplification Factor

    10

    Amplification Factor .............. 10

  • Grid-Plate Transconductance

    5000 uS

    Grid-Plate Transconductance 5000 uMhos

  • Direct Plate CUrrent cvioiceoieiecrieieeseeeeeevnaessseee

    800 A

    Direct Plate CUrrent cvioiceoieiecrieieeseeeeeevnaessseee 800 milliamperes

  • Direct Plate Voltage oo [1]

    2500 V

    Direct Plate Voltage oo ............................. 2500 2000 volts

  • Direct Plate Voltage oo [2]

    2000 V

    Direct Plate Voltage oo ............................. 2500 2000 volts

  • Direct Plate Current [1]

    300 A

    Direct Plate Current 300 375 milliamperes

  • Direct Plate Current [2]

    375 A

    Direct Plate Current 300 375 milliamperes

  • Plate Dissipation [1]

    750 W

    Plate Dissipation ... 750 750 watts

  • Plate Dissipation [2]

    750 W

    Plate Dissipation ... 750 750 watts

  • Undistorted Output [1]

    155

    Undistorted Output 155 85 watls

  • Undistorted Output [2]

    85

    Undistorted Output 155 85 watls

  • Dircet Plate Voltage [1]

    2500 V

    Dircet Plate Voltage 2500 2000 volts

  • Dircet Plate Voltage [2]

    2000 V

    Dircet Plate Voltage 2500 2000 volts

  • Plate Dissipation [1]

    9200 W

    Plate Dissipation 9200 720 watts

  • Plate Dissipation [2]

    720 W

    Plate Dissipation 9200 720 watts

  • Load Resistance, plate-to-plate [1]

    2800

    Load Resistance, plate-to-plate ... 2800 2240 oluns

  • Load Resistance, plate-to-plate [2]

    2240

    Load Resistance, plate-to-plate ... 2800 2240 oluns

  • Load Resistance, per tube [1]

    700 ohm

    Load Resistance, per tube 700 560 ohms

  • Load Resistance, per tube [2]

    560 ohm

    Load Resistance, per tube 700 560 ohms

  • Recommended Power for Driving Stage [1]

    100 W

    Recommended Power for Driving Stage ... 100 100 watts

  • Recommended Power for Driving Stage [2]

    100 W

    Recommended Power for Driving Stage ... 100 100 watts

  • Dircat Plate Current GO0

    720 A

    Dircat Plate Current GO0 720 milliamperes

  • Dircct Plate Current .o [1]

    800 A

    Dircct Plate Current .o 800 800 milliamperes

  • Dircct Plate Current .o [2]

    800 A

    Dircct Plate Current .o 800 800 milliamperes

  • Dircet Grid Current [1]

    150 A

    Dircet Grid Current 150 100 milliamperes

  • Dircet Grid Current [2]

    100 A

    Dircet Grid Current 150 100 milliamperes

  • Nominal Power Qutput [1]

    1600 W

    Nominal Power Qutput ... 1600 1300 watts

  • Nominal Power Qutput [2]

    1300 W

    Nominal Power Qutput ... 1600 1300 watts

  • Direct Plate Voltage [1]

    2250 V

    Direct Plate Voltage 2250 1750 volts

  • Direct Plate Voltage [2]

    1750 V

    Direct Plate Voltage 2250 1750 volts

  • Direct Plate Current [1]

    600 A

    Direct Plate Current . 600 700 miliamperes

  • Direct Plate Current [2]

    700 A

    Direct Plate Current . 600 700 miliamperes

  • Direct Grid Current [1]

    100 A

    Direct Grid Current 100 100 milliamperes

  • Direct Grid Current [2]

    100 A

    Direct Grid Current 100 100 milliamperes

  • Nominal Carrier Power Output for use with [1]

    1099 W

    Nominal Carrier Power Output for use with 1099 modulation ............................ Y00 830 watts

  • Nominal Carrier Power Output for use with [2]

    0 W

    Nominal Carrier Power Output for use with 1099 modulation ............................ Y00 830 watts

  • Nominal Carrier Power Output for use with [3]

    830 W

    Nominal Carrier Power Output for use with 1099 modulation ............................ Y00 830 watts

  • voltage for frequencics between [1]

    20 MHz

    voltage for frequencics between 20 and 10 megacycles should cooling of the glass during operation.

  • voltage for frequencics between [2]

    10 MHz

    voltage for frequencics between 20 and 10 megacycles should cooling of the glass during operation.