On Sat, Aug 23, 2008 at 12:52 AM, Dave N6NZ <[EMAIL PROTECTED]> wrote: > Eric Brombaugh wrote: >> >> What sort of shorts are you seeing? I'm assuming that on a 2-layer >> board they would ordinarily be pretty easy to correct by appropriate >> use of an knife. Or are they internal/inaccessible? Is that even >> possible on a 2-layers? > > You'd think they'd be easy to find. On the board I blindly assembled, > there was a short to the ground plane somewhere. I spent more time than > it was worth looking for it, and scraped away at a couple of suspicious > spots with an X-acto knife. Never did isolate it. On the second > shorted board, it was another short to the power plane somewhere. After > I confirmed it, I just marked the board and threw it in the NFG pile. >
I've had moderate success clearing blind shorts with the 5V bus of a high-power computer power supply. (This can be hazardous to other parts on an assembled board) Otherwise, use a current-limited power supply to put a few amps into the stuck node. Use a millivolt meter to measure different places on it. Lower voltage means closer to the short. Regards, Mark [EMAIL PROTECTED] -- Mark Rages, Engineer Midwest Telecine LLC [EMAIL PROTECTED] _______________________________________________ geda-user mailing list [email protected] http://www.seul.org/cgi-bin/mailman/listinfo/geda-user
