I had been using this Hallicrafters 5R10A for some casual shortwave listening, and the electrolytics had been getting worse, resulting in a constant hummmmmm….. So I figured it was time to replace them. That was the easy part. Replaced the 4-section capacitor with the correct values on a couple of terminal strips. Played fine.
While I have it open, I figured, why not replace the other caps? So I did. Flipped her back over and turned her on…. YIKES! Tons of squealing and motorboating and overloading! WTF did I do wrong!?
Long story short, I had forgotten to run the lead from one capacitor thru the tiny ground-to-chassis loop on the tube socket it connected to. Doh. I figured this out, only after hours of poring over it, poking and prodding with a pencil (this is actually a pretty cool experiment to try, lots of neat things happen!), and moving leads and resoldering.
The lesson? BE THOROUGH! Make sure you connect everything back up like its supposed to be! Take photos! I just “shotgunned” this and really didn’t account for making a dumb mistake like this!
It plays great now, no hum, and the reception is about as good, maybe a little better than before. Took the opportunity to connect a longer set of speaker leads and wire-nut the connection should I ever have to get back in there.[phpbay]“hallicrafters”, 5, 38032, “”[/phpbay]