I used to do hardware maintenance on business mini-computers (before the days of the PC) and one of my favorite methods of finding a short was overfusing. Worked almost every time. Put a 20 amp fuse in a 1 amp circuit and the short would usually be identified (as someone said) by the smoke coming out of it.
One particular exception to this method sticks in my mind. I was working on a check sorter that kept blowing the transport fuse. So I kept bumping up the amperage on the fuse and finally put a 50 amp sucker in there. "That otta find it", said I. Well, it identified the weak link in the circuit...which happened to be the printed circuit board traces on the back side of the power supply. Blew them suckers to kingdom come. That wasn't the problem, tho...just the weakest link in the chain.
The problem was the operator. She was a rather large lady and as she would enter a check amount and drop the check into the transport (this was a Burroughs S200, in case anyone remembers those) she'd inadvertently move her leg and bump the detail printer drawer, which would momentarily disrupt the magnetically operated reed switch interlock...and shut the transport down for a split second. When this was repeated over and over again, the transport fuse (or the circuit board traces) would overheat and blow out.
That one took me a coupla months to solve.
I'm sure glad I write software now instead of fix hardware. It's much less frustrating...even with Java thrown into the mix (I hate Java in case that wasn't apparent.)
