[Elecraft] KPA500 Heat Expansion Pop

[Ron D'Eau Claire]

The Z bracket should be secure and tight against the side of the heat sink.
My KPA500 has 5/16" screws and they tighten the Z-bracket so it does not
move. More recently there have been comments that the 5/16" screws are too
long, and the length of those screws has now been reduced to 1/4" to ensure
they don't "bottom out" against the threaded hole in the heat sink before
they are tight.

I don't know how many kits went out with screws that didn't properly
tighten, but if you are right that would explain it suddenly showing up now.


Ron AC7AC

-----Original Message-----

I think I may have solved this problem. One of the other posts mentions that
the Z-bracket screws are too long and you don't get a tight fit. I changed
the five screws from 5/16" to 3/16" and did notice a better grip between the
bracket and the PA assembly. I have run it all evening and haven't heard a
click or a pop. I even ran the temp up and still nothing. Will it last? I
don't know, but it seems to have fixed it. The guy who suggested this has
submitted it to Elecraft for a change. Good luck and lets hear if any of you
have the same result.