Ok, bear with me.. When I was very young my neighbor had a 4'x8' HO layout ( no scenery) with various loops and elevations. I remeber seeing 1/2 inch-1 inch pieces of atlas track that were I believe insulated on each end and wires solderd to it. I belive that when he ran a train onto this section, it would trip a relay that would route the next switch for it's movement. The layout ran 2 trains without any conflicting moves or accidents. He was an electrical engineer, so this never suprised me. Any idea how it was done, and how could I duplicate that concept. EASILY, CHEAPLY, AND IN PLAIN ENGLISH!! Thanks friends.