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

ACT26

Forced-air-cooled thoriated-tungsten transmitting triode for common-grid VHF amplifier service to approximately 300 MHz.

Directly heatedCold cathodeCommon cathodeDissimilar
Sections
1
Base
-
Socket code
-
Base pins
-
Nominal heater
6.5 V / 105 A

Description

The ACT26 is a forced-air-cooled transmitting triode with a thoriated-tungsten filament for common-grid VHF amplifier service up to about 300 MHz.

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
6.5 V
Nominal heater current
105 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
0.045 S
Max plate voltage
5000 V
Max plate dissipation
5000 W
Max grid dissipation
150 W

Published maximum ratings and characteristics audited; remaining useful numerical data retained in TUBE_SECTION_PARAMETER.

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

1955 Marconi

Published operating points and test conditions from this source.

SECTION 1

Triode

Other

  • common grid circuits at frequencies up to

    300 MHz

    common grid circuits at frequencies up to 300 Mc/s.

  • at a pressure equal to a

    4

    at a pressure equal to a 4-in. head of water. The OF THE ANODE

  • filament seals also require to be cooled by air, and the [1]

    0

    filament seals also require to be cooled by air, and the 0-313'DIA ——I '— BY 0'125"IN ANY

  • filament seals also require to be cooled by air, and the [2]

    -313

    filament seals also require to be cooled by air, and the 0-313'DIA ——I '— BY 0'125"IN ANY

  • filament seals also require to be cooled by air, and the [3]

    0

    filament seals also require to be cooled by air, and the 0-313'DIA ——I '— BY 0'125"IN ANY

  • filament seals also require to be cooled by air, and the [4]

    125

    filament seals also require to be cooled by air, and the 0-313'DIA ——I '— BY 0'125"IN ANY

  • plied through a nozzle. The air inlet temperature

    7

    plied through a nozzle. The air inlet temperature 7

  • should not exceed [1]

    35

    should not exceed 35°C (95°F). All cooling supplies 0-813"

  • should not exceed [2]

    95

    should not exceed 35°C (95°F). All cooling supplies 0-813"

  • should not exceed [3]

    0

    should not exceed 35°C (95°F). All cooling supplies 0-813"

  • should not exceed [4]

    -813

    should not exceed 35°C (95°F). All cooling supplies 0-813"

  • voltages, and should continue for at least [1]

    30 V

    voltages, and should continue for at least 30 sec. after s. tn ] 1 _E;—Ln 175

  • voltages, and should continue for at least [2]

    1 V

    voltages, and should continue for at least 30 sec. after s. tn ] 1 _E;—Ln 175

  • voltages, and should continue for at least [3]

    175 V

    voltages, and should continue for at least 30 sec. after s. tn ] 1 _E;—Ln 175

  • Filament Starting. The cold resistance of the filament = i >

    3

    Filament Starting. The cold resistance of the filament = i >3

  • is [1]

    0 mA

    is 0-0064 Q. The filament current must never exceed

  • is [2]

    -64 A

    is 0-0064 Q. The filament current must never exceed

  • I

    105

    I 105 A ANODE. \ /

  • At frequencies above

    100 MHz

    At frequencies above 100 Mc/s the permissible anode

  • voltage must be reduced to the following percentages of [1]

    50 V

    voltage must be reduced to the following percentages of 50 *0-063"

  • voltage must be reduced to the following percentages of [2]

    0 V

    voltage must be reduced to the following percentages of 50 *0-063"

  • voltage must be reduced to the following percentages of [3]

    -63 V

    voltage must be reduced to the following percentages of 50 *0-063"