Here is a trick or two that may work: feed a very small AC voltage with say 1KHz and 10mV into the bad power rail. It won't hurt anything.
Then use an old cassette players' magnetic pickup and amplifier to follow the signal to the short. No need for expensive hall effect meters. Another trick that I often use is force-feed power into the bad power rail. If it's a 5V rail, then say 5V at 2A. That can work by having the bad part get hot really quickly, by allowing you to DC probe with a millivolt setting, or it can backfire if it's a tant cap by blowing it up. I would use that only as a last resort if the first trick didn't work, as the second trick can be dangerous! So please be careful, any repair should be done only with proper equipment (using a 110V isolation transformer for example)... bye, Said In a message dated 3/23/2012 14:13:57 Pacific Daylight Time, j...@quikus.com writes: Are there Hall Effect probes for chasing DC faults? I'm very familiar with the HP Logic Current Tracer, but AFAIK that is only sensitive to fast pulses, from the Logic Pulser for example. The threashold is adjustable, so maybe it will sense DC currents. If it is DC sensitive it'd be even more wonderful. I'll try it after dinner. Thanks, -John _______________________________________________ time-nuts mailing list -- time-nuts@febo.com To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.