[Elecraft] KPA500 problem

[Mike Crownover]

I just bought a lightly used KPA500. It arrived from the seller, well packed
and complete with cables, manuals, etc. I turned the amp on, interfaced it
with my K3, keyed the radio and the KPA500 immediately shut-off. No fault
light or error code, nothing. It shuts down just as if I had pressed the
power button, the fan runs, etc... The antenna is resonant 1:1, I've lowered
input power to 10 watts, swapped coax, hooked it up to another K3, used RCA
to RCA cable, the Elecraft cable, etc.. When down to 10 watts input, I can
tap the paddle like a straight key lightly and the amp works, but put two
dits together and it shuts down.

 

Has anyone had an experienced anything like this. I keep thinking this has
to be something simple.

 

Mike AD5A