[Elecraft] K3S - No high power output - Low power OK

[Ken Bolin]

My K3S is about 3 years old and is S/N 11185. It has operated flawlessly
since it got out of the box.

 

I was using it this weekend in the VHF contest and operated perfectly until
Sunday afternoon. I took a break for dinner and came back about two hours
later and found that I had no power output. The radio was left on during
that time. There was no indication that there was a power surge of any kind
and there was no smell of anything electrical. Since I wasn't transmitting
during that time, there was no SWR issue.

 

After doing some initial troubleshooting, I found that the rig worked
perfectly at low power but when I go above 9 watts (12 watts on HF) I get no
output. The display indicates two dashes where the SWR is displayed and the
power indicates 0.0 W.  When I try to transmit with higher power, the red TX
light comes on steady and the K3S also keys my amplifier properly. I've
tried it on several bands with the same results.

 

The only other thing of interest is that when I came back to the rig after
dinner, the rig tried to transmit in CW while receiving in TX Data. I did
not leave it in that configuration. That may indicate that something my have
happened with the S/W settings.

 

Any suggestions of where to start looking

 

Thanks

Ken W1NG

w1ng at snet.net