[Elecraft] K2 Problem

[VR2BrettGraham]

W3FPR continued:

>Rather than looking for similarities, you may want to look for potential
>ground loop sources.  Those ground loops are really 'sneaky' and can cause
>strange effects.  Locating the real source can be a grand problem in itself
>because there are so many possible 'sneak' paths.  I wish you luck and good
>troubleshooting.
>
>One 'help' I can offer -- see what happens when transmitting into a dummy
>load -- that will eliminate the possibility that RF-in-the-shack could be
>the root of your problems.
>
>Sorry, but there are no 'simple' answers.

Yes, not simple - change nothing but the radio & problems
start.  Not the thing one wants to experience in the heat of
doing something important.

Difference between K2 at max & KPA100 at minimum
should not result in significant difference in RF environment.
Two radio contest station in apartment is pretty extreme, but
K2 with no special precautions has been fine - could never
do SSB with OMNI-6 without an isolation transformer &
serious work on rear panel spigot EMC improvements.

I still believe the rig has developed a fault whilst in storage &
perhaps it's all related.

BTW, I have posted to the list before my observations of
noise as result of computer control of the radio.  In listening
to myself on second rig when frantically trying to find some
new cabling-related fault, it was clear there is a significant
amount of noise being transmitted by K2 that is the direct
result of KIO activity.  Mine, after small 400 watt amp, puts
out what looks to be several watts whenever K2 is polled for
frequency info.  Now I know I can't use computer control when
on SSB until I find the root cause of that.

Transmit audio also sounds lousy in general as compared to
after I changed compression ratios a bit - all combined, if not
so busy trying to keep run going whilst troubleshooting,
probably would have chucked K2 out third floor window.

But last time when in use, same K2 in same side of console
with same cables, same this, same that & same the other,
didn't do any of this (except transmitted KIO noises).  Bit
busy with other things & need good CW rig for CQ WW CW,
so fingers crossed part of problem here is like that at K0ARO
& therefore may help get to the bottom of it all in time.

73, VR2BrettGraham