[Elecraft] KPA100 Parasitic on 40m

[Don Wilhelm]

Jonathan,

I suggest (strongly) that you upgrade that KPA100 with the KPA100MODKT, 
it was specifically targeted at the problem you are having.
Also, if your shield kit does not have the side clips and solder lugs to 
ground the shield to the SO-239 jack, get a new shield kit too.  Earlier 
shields had a wider slot above the SO-239 jack and caused problems along 
with RFC10.

73,
Don W3FPR

Jonathan Taylor, K1RFD wrote:
> I had originally posted a question about this problem back in 2006 and I 
> am re-posting it because the problem persists, and I'm wondering if 
> there might be an updated suggested fix.
>
> The issue is that my K2/100 #2462 is frequently unusable on 40m at high 
> power.  When going into TUNE, it often blows the fuse.  This happens 
> with or without the KAT100 connected at various times, and with various 
> loads, including a dummy load.  The conclusion from earlier discussions 
> is that this was probably a parasitic oscillation in the PA.  I have 
> tried N0SS's suggestion of shifting the position of RFC10, without 
> success.  I have the Rev B KPA100 board.
>
> Thanks
>   
>