[Elecraft] KPA100 Issue

[Eric Swartz - WA6HHQ, Elecraft]

Folks - Please do not replace the thermal pads with heatsink compound on 
the KPA100. As designed, the material on the pads flows slightly as they 
are heated up during transmit for the first several times, filling in 
the small gaps between the transistors and the heatsink surface. That is 
why we note that your should tighten the screws after your first several 
hours transmitting. Once the initial flow has occurred and you have 
tightened the screws there should be no need to tighten them 
significantly in the future.

73, Eric   WA6HHQ
Elecraft


Dave & Jeanne Robertson wrote:
> Thanks for your reply Geoff.
>
> I think that the reason the screws loosen isn't because of twisting 
> out, but because the heat sink material that is placed between the 
> power transistors and the heat sink is cold flowing.
>
>