@Adriatic posted:
The DIFFERENCE when hot is more important. You might also look for a voltage difference with a meter on the coil wires. As heat expands a coil, breaks/cracks/nicks can stretch apart, thinning before breaking creates more heat and resistance. Eventually it may expand enough that a gap forms when hot, then reconnects when cooled, then disconnects, etcetc.
You implied the issue cleared up with the ZW on the test track. That is a clue that pointed at supply regulation type more than anything. (unless I have thermo mixed up. hard to tell with lionel what is NC or NO at times)
Capacitors, diodes, resistors, and maybe a relay or transistor or opto isolator.... like adding a cap. discharge to a turnout.
In this instance, the coil doesn't create that much if any heat that one needs to worry about that. Capacitors, diodes, resistors, relays and transistors ad nauseum aren't necessary to make this circuit work. The technology is sound, and as I noted above, one only needs to understand its principle.
