[Elecraft] K3S KRX3 carrier-operated relay noise at 20w plus... gets louder

[M. George]

I'm pulling my hair out on this one... all morning trying to do my due
diligence.

I picked up a used K3S which is like new... I got a great deal.  Anyway, I
verified with Elecraft that this K3S was factory assembled and there were
not any field upgrades installed based on the verification of the original
invoice with Elecraft.  All the goodies with the factory build are
installed.

The first thing I did when I got it was to reset all the settings back to
defaults and then take the time to go through setting everything up again
and running through all the calibrations etc...  It would have bugged me to
not know how everything was setup, plus I have done this many times over
the years with K3 kit builds etc...

My (new to me K3S) has the KRX3 installed and everything is working as
expected, except that I'm hearing the carrier-operated relay come on when
keying CW into a dummy load on ANT1.  I have verified that the KAT3A which
is installed to is not setup to send any RF input to the KRX3, but the
standard build is in place with the AUX RF BNC connector is connected
directly to the back of the KRX3 input.

I don't have a receive antenna hooked up to the AUX RF connector and in
fact I have put a dummy load on it just to be sure there shouldn't be any
funky RF getting into the KRX3.

I setup the CONFIG KRX3 setting to Ant=bnc and I have powered off the radio
and back on etc... but I still get the problem with the carrier-operated
relay coming on.  There is some info in the manual about an issue with VCO
CAL needing to be run again if you have this issue, but I don't believe VCO
CAL applies for the K3S with the new synth boards.

I have a solid dummy load connected to ANT1 and I just can't see what would
be causing the carrier-operated relay to start to switch on as increase
 power to the +12 watts point where the KPA3A kicks in.  I can start to
hear the relay to start switching around 20 watts plus as already mentioned.

Hmmmm, any thoughts... hope someone made it this far into the post.  I hope
I'm not having an RTFM or STFI moment here and missing something obvious.

Max NG7M

-- 
M. George