[Elecraft] K2 Help need

[Don Wilhelm]

Gregg,

That definitely sounds like your KPA100 is oscillating.  Do not allow it 
to do that for more than a few seconds because the oscillation can cause 
the demise several components.

Has your KPA100 been upgraded with the KPA100UPKT?  Alternately, is this 
a new KPA100 that was shipped in the last 2 months of last year?

If the answer to both those questions is 'NO', then I strongly recommend 
that you add the KPA100UPKT as the first order of business.

If the answer to either question is "YES", then please physically 
inspect KPA100 C31 - if it is not a .22 uF capacitor, then obtain the 
proper .22 uf capacitor from parts at elecraft.com and replace it.

73,
Don W3FPR

w6izt at bellsouth.net wrote:
> I am current operating /KH6 and my K2 has developed a problem (it was working fine.) I am using a K2/100 with the KAT100 tuner. The problem only occurs on high power.
> 
> The KAT100 tunes the antenna to a near 1:1 swr on all bands. Key down all is OK, on key up the swr jumps to a very high level, this occurs on all bands. I am guessing the KPA100 is going spurious on key up.
> 
> Any ideas on where to look for the problem, other than generally in the KPA 100?