Re: "For the record, the time I did it was in a DEC H754 -15V regulator brick (which is, of course, a switcher). I had it on dummy load, so I knew it wasn't really being asked to supply too much current, but there was no output. I lifted the collector lead of the current sense transistor and switched on. BAD MISTAKE!. The crowbar was firing (incorrectly, the zenner diode had failed), so there genuinely was an overcurrent situation. The result was that 4 of 5 transistors fialed (some were blown apart), the current sense resisitor burnt out (I think it actually glowed) and the fuse blew." Isn't it amazing how nasty electricity can get once you get it pissed off?