On Mon, 3 Apr 2006, Sean Schouten wrote: > On 4/2/06, Peter wrote: >> >> That zapper is not good for the RFIDs used in shops afaik. Also it's >> more than a few months old and I happened onto it by accident. Someone >> looking for the right keywords must have discovered it a long time ago. > > I have yet to explore RFID-chip datasheets, but wouldn't you think that > atleast the leading RFID manufacturers would have some sort of EMP-overload > protection (voltage clamping?) built in to their products? Especially if > their chips are designed for the harsh industry enviroments... The simplest EMP protection is that of having none. If someone zaps the chip in an object and it is subsequently discovered that the object has a non-responding chip then the cashier or equivalent will tap it in by hand, by EAN or barcode, as usual. This is not a problem for the shop or the system. Think about how many times the cashier has to tap in the EAN because the barcode reader does not work on a product (about 5% bad reads are valid even by barcode reader manufacturer standards for a variety of reasons). Anybody who expects to be able to walk out of a shop with, say, a bottle of milk, without paying, because the bottle's barcode did not register at the cashier's needs help. Peter -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist