I would strongly suspect that the transformer (if connected to mains) is the source of the 80Vdc. No mains connection is entirely free of transients and noise. There also may be some nonideal characteristics in the transformer such as capacitive coupling between the primary and the secondary. --=20 Jason White --=20 http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist .