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ACT29B / BR1138 power triode

Size This valve measures 460x180mm overall.

This is an HF air cooled triode.

Filament voltage 8.5V
Filament current 20A
Max anode voltage 10kV
Max anode dissipation 1kW
Max anode dissipation (forced air cooling) 1.25kW
Max grid dissipation 80W
Max peak cathode current 5A
Max RF grid current 14A
Max frequency (full ratings) 15MHz
Max frequency (25% anode voltage) 80MHz
Amplification factor* 40
Anode impedance * 12900 ohms
Mutual conductance * 3.1mA/V
Capacitances
Cgf 23.2pF
Caf 1.6pF
Cga 15.9pF

*: At Va=5kV, Ia=200mA. NB the above ratings are for the ACT29; the 'B' suffix may indicate a change to these figures.

Inside view

ACT29B

Connections: The anode has two strap connections just below the cooling fins. The grid connects to the base shell and the filament to the two pins.

Top quarter view

Top and bottom quarter views of the valve. See below for details of the cooling fins.

Bottom quarter view

Cooling ring

Above: One of four sets of cooling fins assembled. There are 20 fins per ring and 4 rings in total. Below: The fins themselves. The cut-out is to alllow access to the screws holding the assemblies onto the anode.

Fins

FIns being assembled

Housekeeper seal

Above: The glass to metal seal.

 

The ACT29B without its cooling fins.

ACT29B without cooling fins

Donated by Bryan Lonsdale

 

This file was last modified 23:12:31, Saturday June 07, 2008