Why does it just shock the cat on the ear and not the tail or middle of the back or any part of the cat? I mean, it is the same cat. I did do some experimentation. If the cat is sitting on the wooden kitchen table, no problems. But if I put the cat on our fuzzy sofa, then stroke stroke ZAP! So... 1) It has something to do with that sofa, and 2) something to do with the ears. As for the sofa, man, at night I can drag a fuzzy blanket over it and me and see sparks galore. >>> Lindy, the cats fur is an extremely good insulator. when you pet it you collect charge on your hand. the more you pet it, the more charge you collect. when you get to the ear where it doesnt have that fur, you discharge your hand through the ear (charging the body of the cat). try standing barefoot on a non isolating surface, or touch some big metal part (ouch!) before touchign the cats ear. Just dont go near a PIC microprocessor after petting your cat or you might program it in a way you dont like. ;-) Lembit > -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist