[Elecraft] KPA100 Upgrade Problem

[Jim Brown]

In preparation for the K60XV I just finished, I had to upgrade my 
KPA100. It involved changing a few resistors, adding two jumpers, and 
replacing the firmware. It's now shutting down when I go into tune 
mode (with the KAT100). I smelled smoke, and R21 in the KAT100 shows 
signs of overheating. I've pulled it back apart and looked for 
shorts, wrong component values, or other problems, but found none. 

Any ideas?

Jim K9YC