[Elecraft] K2 - Low output on 10m

[Bill Coleman]

When I first built my K2 this past March, I followed AB7MY's instructions 
and wound T2 with lots of core coverage, spacing it just off the PC 
board. I was pleased when I got over 12 watts on all bands, and 11.5 
watts on 10m, since I planned to get the KPA100. 

Recently, though, I was diagnosing a problem where I had no output on 
80m. Turns out I had a PTTL (Poorly Tinned Toroid Lead) on L17, and the 
80m low-pass filter wasn't connecting to the antenna anymore. A wee bit 
of soldering fixed that problem.

I decided to check all bands, and found that I could still get 12 watts 
on all bands, except only 6.5 watts on 10m, and 10.4 watts on 12m, into a 
50 ohm dummy load. 

I re-tuned the receiver front end coils and caps for maximum TX output, 
but there was no change for 12/10m.

Any suggestions as the best way to diagnose this fall-off in power output 
on the higher bands?


Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr@arrl.net
Quote: "Not within a thousand years will man ever fly!"
            -- Wilbur Wright, 1901