[Elecraft] K3 sudden loss of RF power output

[Missouri Guy]

Hi Gents,

K3 sudden loss of RF power output:
I was operating the FD event over the weekend...had a nice
pileup going...I heard a "pop" in the headphones and discovered
that there was ZERO RF power output when there should have been
100 Watts.  Receiver was OK and the radio was otherwise "acting" 
normally as when switching from receive to transmit.  
Circuit breaker not tripped.

I want to do some troubleshooting before (and if) I send the
radio to Elecraft.   Per a Google search, this has happened
before to others and a bad Q8/Q9 and R66 on the RF board 
might be suspect.   Anything else on the list?

Thanks,
Charlie, N0TT