Stereomour Diagnosis Testing or Repair?

[audiotecture]

Paul...DC voltage at OA = 212.1V & DC voltage at OB = 209.7V. The jumper between terminals 7 and 9 worked sound came out of both the A-side and C side. I checked all of my wiring and connections from the RCA jacks to the selector switch and selector switch to the volume pot and volume pot into amp. Almost perfect good news. RCA jacks 2 & 3 are sending a signal to both speakers. RCA jack 1 is still only sending a signal to one of the speakers. I don't have any more time tonight to troubleshoot RCA jack 1, but I'm assuming I'll just need to re-check all my solder joints and connections. Is it possible to damage an RCA jack during soldering?

 

[Paul Birkeland]

Yes, you can damage a jack.  If solder flows between the center of the RCA jack and the shell, it will short out the signal.  99% of the time, this is what we see going wrong.  If you measure the DC resistance between the center pin of the jack and the outside body of the jack with the selector switch not on that input, it should give you a very high resistance (or over limit).  If solder has shorted the jack out, then you'll see something close to zero ohms.

I have also seen debris get into the bottom side of the jack between the center pin and shell, and that was enough to create the same problem.