40m QCX finished

 

I finished my QCX 40m kit yesterday. The alignment went well (I think, It's hard to know what "numbers" I was supposed to see. I finally got to the point where no further adjustment would improve anything).

No complaints but I have a couple of observations- the two jacks for the key and audio don't line up. It took some fiddling to get them both installed. They are both off by a few degrees. The only real concern I have with it (other than aesthetics) is that I bought a case for the QCX and I'm not sure what kind of problems that will cause when I try to install it. I vaguely remembering that this was the case with the first round of boards. Something isn't right with the jack or the footprint. The transformer, while not fun to wind, was pretty easy to wind by following the instructions. I would have bet money (like $0.01 US) that it was going to be a pita to install but nope, it was not much different than installing a toroid. 

I was an early adopter of the QCX (and WSPR rigs) and I think the first one of these that I built was the 80m version. It didn't go well. The same brain cell that sees 1°-2° as "horribly off" never reconciled the windings being stacked on the transformer and I'm pretty sure I completely hosed up the winding of the transformer trying to make them "perfect". I also had a very tiny solder ball across two of the leads of the MPS751 (found that with a microscope). I desoldered and re-soldered or replaced so many things looking for the problem that the solder ball was causing that I ruined the board (I think, it's still here somewhere. I may see if I can turn it into a different band just for fun).

I think my firmware is one rev off. I've never had much success with flashing firmware but maybe this will be the first good result.

For some reason my printer was giving me fits and it would skip a page every now and then. I didn't catch that until I was well into the build. One of the pages that it skipped was page 17, Install DIP Integrated Circuits. I kept wondering why the IC's weren't installed with the IC socket (they were supposed to be). The good news is that it's not too hard to install them after the board is populated but it's definitely good to install them in order. 

All in all these are great little rigs. I enjoyed the build process. The kit was well packed. All parts were there. The board quality is high. 


--
73
NE5U

Mike

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