> > And why 1N4148s are dying, 1N4007 not? Interesting question. Obviously the 4007 can handle more energy, but that's not likely the cause. I'd wonder about the wiring between the transistor and relay, maybe another sort of transient happening at much higher speed.. This is the sort of thing that gets interesting :) -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist