[Elecraft] KAT100: Strange K2/100 Behavior During Tune

[Jonathan Taylor, K1RFD]

I have a K2/100 with a KAT100.  For the most part, all works well as 
expected.

Intermittently, though, when I press the TUNE button, the KAT100 will 
chatter briefly as if finding a match, and then it suddenly stops and the K2 
acts as if its CPU has been re-set; the bargraph and the LCD go blank 
briefly, then the ELECrAFt sign-on message appears briefly and finally the 
frequency is re-displayed.  During this time, however, the power supply 
indications are normal and the LCD backlight remains on.

This problem seems to be frequency-dependent and seems to happen more often 
at high power, which leads me to think it is an RF feedback issue.

However, I've noticed that turning the power down to bottom end of the 
high-power range (approx 12 W) usually doesn't help, yet turning it slightly 
lower than that, to get into the low-power range (approx 10 W), does.

Any advice on how to solve it?

Thanks