[Elecraft] k2/100 problem-help

[k6xr]

k2/100 and kat100 all working great on all bands at all power levels for
months. Then two days ago I could not get the kat100 to hold swr after
tuning. It goes all over the place causing power supply,and the  k2 to shut
down along with hi-reflec and hi-current.

This occurs only on 40 meters. There is no problem on any other band or
frequency. Now comes the strange part. If I pull the kpa100 dc cord, I can
run the qrp and kat100 at 15.2 watts on all bands all frequencies with no
problems forever! But if I connect up the dc cable, the problem starts at 14
watts and the kat/k2 go crazy on 40 meters.

I have tried 3 different power supplies in different locations 6 feet or
more from rig.
Changed or checked out  all coax jumpers, Balun, ladder line, and antenna
and ground.

I can hook the k2 to my mfj-993 auto-tuner and there is no problem, it all
tunes fine with the kpa100..
I can manually tune with no problems with the kap100 powered up as well.

Is it possible to have a problem with just 40 meters  on the kat100?  H s
anyone else ever experienced this?

By the way, I have a ts-570 coax switched into this same antenna setup and
no problems with the switches or coax or antenna or it's parts.

Help!
 
Reggie k6xr
k2/100 4112

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