Thought I'd pass on a hair raising experience to the club.
During a recent string change on my SC Standard, I noticed the 1/4 input jack nut was pretty loose, so I tightened it down and went on with the set up. After I'd gotten things all polished and tuned, I got called away and couldn't really get into any heavy noodling.
A few days later, I plugged in and noticed that rotating the pickup pan knob from center detent toward the bridge p/u had the effect of reducing overall volume, i.e. all bridge p/u = no output. I was getting all neck p/u out the cable.
Bad taste in mouth.
I opened the backplate, put in a fresh 9V just for kicks (it had been a year), and looked for any obvious signs of doom. No smoldering embers, no loose wires, no rodent hair. Plugged in again. Still no bridge p/u.
Ewwwww.
Putting myself into Undo mode, I retraced the steps of the last string change and thought back to tightening the input jack nut. Sure enough, tightening the nut had rotated the inner jack bits into the circuit board of the bridge p/u (apparently making it very sleepy). I hadn't noticed this when first staring into the cavity -- panic and dread plays tricks on the eyes.
I realigned the jack. Voila! The bridge p/u was as right as rain.
Mica 'splained to me that it's a good idea to secure things from inside the cavity when tightening the nuts. Why didn't I think of that?
