[Elecraft] Low pwr problem

[Rick]

It was late last night when I fired up the KPA100 for the first time.  IT
WORKED FINE!  The smell of electronic inefficiency filled the air (burning
paint, I guess). I heard my power supply groan for the first time! It was
good. But I digress.

I am one of those guys that is too good to read ALL of the instructions. In
the final minutes (no pun intended) before intitial launch I could plainly
see where all the wires and cables were supposed to go, so I placed them
without checking the instructions. I sort of did, I think. I checked the two
supply scenario and all was o.k., but I was sort of winging it. No problems,
though.  RF watts got directed into the dummy load where they belonged and
lots of radio energy made and wasted. Happy Day!

Then I put the QRP lid back on the rig (internal tuner, et al) and fired up
the rig to see if it was still a QRP radio.  Yup, but now one limited to
about 1 watt on 80 and 40, and maybe a few hundred milliwatts on the higher
freqs. The display indicated "Lo pwr", but I knew that. Hmmm.

I took out the control board and reset the relays.  I checked voltages. I
removed the driver and finals and checked them.  I checked R50.  I checked
everything and everything was fine!  I even bypassed the BPFs and got rf out
of pin 3 of the output xfrmr and still got just a watt.  I removed the SSB
adapter and bypassed it. When I did this the output power dropped to just
half a watt on 40 and 80! Hmmm. At least it was a change but it happened at
3 a.m. so I gave up and went to bed.

This morning I had an epiphany (and a bowl of oatmeal with raisins). I
reinstalled the SSB adapter and its old microcontroller (you get a new one
with a KPA100).  The power was restored! The K2 was back to it's original
0.1 to 15 Watt self!  Happy Day II.

Then I put the "new" microcontroller back in the SSB adapter. It worked
fine! Hello?

I don't know what caused the problem and I am confused about what fixed it.
I didn't read the last few lines in the manual. Does Elecraft know when you
don't read all of the manual?  Was it a warning from the QRP Gods? Any help
would be appreciated.

Rick
KC0OV
K2 1360