Hi, Brian

One of the "common" (squeaky wheel, probably less than 5% of the radios) problems in the earlier QCX's was that the volume control "legs" didn't quite make it to the board. In most cases the "solder blob" would make the trip, but occasionally one or more legs would be open. One extreme would be no audio, if the top or middle legs were open, or no control over audio, if the bottom leg was disconnected. What could have happened with yours was that the wiper connection was just touching and disconnected itself during handling. So maybe it wasn't your clumsy part replacement work. If you still have the board out it probably wouldn't hurt to do a touchup on the volume control connections.

73

Jim W4JED

Early this year I bought a used 40m QCX... nicely done with the German metal case.

But... it was an earlier model with the 10uf electrolytic caps in the audio filter chain... way to much keying click for me. So I left it as it was for the time being. Weeks later I made a journey to our local small shop selling electronics.. it serves the universities here for student and staff projects in engineering and tech need.

I got .1 and 1 uf caps.. as there were many suggestions on replacement value. I know that 1 uf is the recommended at this time.When I got the quiet time to remove the 10 uf caps and put in the 1 uf it sounded fine. UNTIL I got the replacements soldering in. NO audio. Hmmmm.. worked fine to this point. I left it for further pondering as summer wafted by.

So today I looked. Well, first thing.. of those two caps to be 1 uf.. one was a 473 marking... not 105. What! How did that happen?  So I put in a 105 ( I uf) cap. Still not working. I hear a very weak sidetone when keying though.

So... I get out Hans' manual on the computer (we all know how good it is). And I trace thru the CW filter and audio chain. Look for continuity etc. Not getting continuity from the wiper of the audio level pot and the leg of C22 that should be there. So I solder in a jumper from terminal 2 (wiper) of the audio pot and the leg of C23. All works! AND-------- NO KEY CLICKS!!!

So I think that last little bit of lead insertion, removal and replacement at the hole for C22 must have lost its connection to trace to the wiper. No problem, I will just put in a tidy permanent jumper and have a rig for the winter.

And as it happened.. while looking for SKCC contacts today I worked a guy who had just finished his 40m QCX and I was his first contact on the rig. His signal was just as good as any of the general 'average' signals on the band as well. Good for him.

73

Brian VE3VAW Toronto