You'll just have to drink chilled beer and put ice in the whiskey - to stop it evaporating of course. My diagram I posted, would give a bi-directional occupancy detection, that providing the power didn't go off, would stay on until the loco / train left the section. If it was to be used in a fiddle yard loop, with single direction travel, then only 2 reed switches would be required, one to trigger the occupancy relay (green) and one to clear the line (red). Old school relays and reed switches, no dark side (you've got to put the right bait on to get them hooked ) Of course you could always feed the reed switches into an Arduino, but that's another story Paul
Thanks Paul, Chaps, if you don`t have the set up to be able to straighten wire etc. and do the whole thing from scratch, Paul`s method is an easy over the counter solution to achieve the same result. In fact it is a more complete solution......... http://www.clickGormo