> I'm taking on my first home-built amp. It's the Granberg Motorola EB104
> design (600W from four MRF150s; basic circuit looks like the Ameritron
> ALS-600). I've assembled kits before but don't have a clue about building
> a
> heat sink from scratch. How do I go about attaching the RF transistors to
> the PCB, copper spreader and aluminum heat sink?
>
> //Normally, the transistors attach directly to the heatsink, using their
> mounting screws, with thermal grease between the transisor and the sink.
> If you have a copper spreader, of course that gets securely sandwiched
> between the transistor bases and the aluminum heatsink, using thermal
> grease at all interfaces, and still gets all screwed together. The PCB
> should have holes in it where each transistor mounts. Only the transistor
> C-B-E tabs actually attach at all to the PCB -- the base of the transistor
> doesn't even touch the board. Sounds like you don't have the board on
> hand to look at.....-WB2WIK/6
>
>
> Thanks. Don November-Alfa-Six-Zulu
>
> --
> Don Putnick
> dputnick@alumni.caltech.edu
>
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