Re: 20 meter QCX-- 1/2 watt output

Axel
 

Michael, did you solve the problem?

I measured the square wave voltages on IC3 at key down:
Pin3: 5.0 V
Pin4: 3.5 V

I have 2.9 W out at 13.5 Vdc. 20 m. I had to replace C25 and C26, same value (390 pF), NP0.

Do you have ~12 V supply voltage even on key down?
If you want to replace IC3: I found a toothpick very helpful in removing the solder out of the holes.
I use a cheap socket for IC3 without problems.

73
Axel, DF1ET

Join QRPLabs@groups.io to automatically receive all group messages.