There is room for the filament transformer without going outside (tacky). You
can add to the base voltage of the original transformer. When I installed 2x
3CX800A7 tubes and another control board, I moved the original transformer over
about 3/4" and stacked twoo smaller surplus transformers to get the required
voltage. There are also some toroid filament transformers that are small.
Just need to be creative. The tube can be recessed in the tube "box". You
have to do mechanical work to install two 3CX800A7 tubes into the two hole 76A
because the anode fins overlap using the original holes. They can pop right in
a 3 holer, though.
I might try using a GS-35B if the 8874 tubes ever wear out, but I run the amp
at 1200 watts output and the tubes may outlast me.
73, Colin K7FM
_______________________________________________
Amps mailing list
Amps@contesting.com
http://lists.contesting.com/mailman/listinfo/amps
|