> When dial phones were king, exchanges were often "Step by Step", > although there were other systems, but most would have used a > I had a piece of Step-By-Step (I think it was a uni-selector) as a door stop, but sadly it disappeared in a move. I remember working in crossbar exchanges and listening to the rhythmic ebb and flow of calls as they were making their way thru the system. From memory there was always a big increase in calls a bit before lunchtime. Justin --=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 .