FIXED IT!? After way too many hours today I finally fixed the problem. It turned out that Q1 had failed. I only found this after replacing Q4, Q5 and Q6 again. After that failed to bring back the TX I suddenly realised that Q1 was getting hot even on receive. I has previously replaced Q1, Q2 and Q3 before I replaced IC3, so either the? replacement was faulty or the failed IC3 cooked it.
Either way, it is now working again and I got a quick 599 from an Italian in a contest this afternoon just as the band was closing.
Anyway, thanks all of you for your help.? So it looks like using the radio on WSPR cooked the 5V regulator. This in turn took out IC3. This may have then caused Q1 to die, not sure about that though. I do think that an IC socket on IC3 would have helped replacement a lot.
Now Jim G3YLA and I have to give a talk about the QCX to Norfolk Amateur Radio Club on Wednesday. So glad it is working!
Steve G0KYA
