just a quic question. Layout is gonna have 2 reverse loops . do i need an extra direction switch for each one? oh also. can you rig up a atlas snap relay to act as a direction switch ?
In wiring a DC reverse loop, a lot depends on whether it's a true balloon loop (like the dialog balloon in a cartoon) or a diagonal connection between the opposite sides of an oval. Also critical is the desire to have your train run continuously rather than stop while you 'reverse the world.'
The dead-simplest is to stop the train with both ends inside the isolated (both rails) section of the reverse connection, then either reverse the track on which the train is standing (and the locomotive reverse switch) or the main line (in which case the locomotive reverse switch should NOT be thrown.) Reversing the main line is also possible while the locomotive continues to move in its original direction.
It is possible to wire the reversing sections directly to the power supply output without a separate reversing switch - if you have a separate 'direction' switch for the main line. ('Direction,' in this context, means railroad direction - north, south, east, west - not locomotive forward or reverse.) Effectively, this makes the main line the reversing section, while the reverse loops become constant-direction tracks.
This can get VERY complicated in a hurry. I've barely scratched the surface.
Chuck (Modeling Central Japan in September, 1964 - with one reversing section)