[Elecraft] K-1, KAT1 help needed

[Peter Broida]

I assembled the K-1 and it performed flawlessly.  I then assembled the
KAT1 unit, installed it, and the K-1 ceased to function.  Even when I
remove the KAT1 board, the receiver is all but dead (I get hiss and I
can hear a weak carrier from my Icom 756 Pro, and I can hear a weak
carrier from the K-1 in the receiver of the 756 Pro).  The K-1 and the
KAT1 are the latest revisions, firmware, etc., purchased just a couple
weeks ago.  I've checked the archives for similar problems, and see
nothing on point. I do not have the equipment, or expertise, to do
elaborate troubleshooting.  Any suggestions will be appreciated.

Peter
K3SFP