[Elecraft] KX2 with KPA500 and KAT500

[Len Chesler home email]

Happy new year to all!  I am curious to know if anyone on the reflector has experienced this issue.  I occasionally like to use my KX2 at QRO power.  I have the ACC output of the KX2 interfaced to a KPA500 which is interconnected to a KAT500 antenna tuner.  When the tuner is not powered, the KX2 and amplifier work perfectly with over 150W output.

When I power up the KAT500 and switch the amp to “oper” mode, the receiver in the KX2 desenses rendering the combination inoperable.  When switching back to “STBY”, the receiver is back to operating normally.  Turning off the power to the tuner allows normal operation.  Not sure what is happening. Any suggestions?  Tnx. Len