[Elecraft] [KX3] Unstable SWR reading

[Gary Hawkins]

On my last two portable outings I've noticed that after a few QSOs I 
start to get unstable SWR readings, with the radio reporting fluctuating 
SWR ranging into the 2 and 3's.  I'm using a tuned antenna, plus 
pressing the ATU button results in 1:1 matching. Everything is fine for 
a while and then the SWR reading go unstable midway through the QSO.  
Pressing the ATU button seems to resolve the problem for a while but it 
starts up again.  I realize it could be a problem with the cabling or 
antenna but visual inspection seems to indicate everything is fine and 
so far I've not been able to replicate the problem on the bench.  Has 
anyone seen this type of problem with the KX3?