As far as I know, it does not have to be run on a twisted pair, but it usually is so that any distortion that is applied to one line is applied to both, this distortion can then be filtered out at the recieving end. If you have the wires close enought together, I don't see why it should make too much difference if they are twisted or not. Mark Hankins ===== Please take a while to visit this page: www.geocities.com/markosaurus/index.html ____________________________________________________________ Do You Yahoo!? Get your free @yahoo.co.uk address at http://mail.yahoo.co.uk or your free @yahoo.ie address at http://mail.yahoo.ie -- http://www.piclist.com hint: To leave the PICList mailto:piclist-unsubscribe-request@mitvma.mit.edu