@Bryant Dunivan 111417 posted:
I Remembered the resistors were recommended by Custom Signals. The resistors had to do with his system. I have diodes on each also. Good insurance for sure.
Actually, I believe the resistors have to do with a possible derailment and spikes traveling up the non-derailing leads and killing the DZ-2500. That came right from Dennis Zander, so I suspect it's probably the real reason.