On the 1:1 railroad there was a 10,000' limit between the Harris boxes on the lead and DPU's without a repeater in the middle. Our Harris boxes are RP modules. Does anyone know how far apart two LM's can be and still communicate?
No idea, but I imagine that it is the same distance between the HC and LM, which can depend on environmental variables (physical obstructions like walls or tunnels, airwaves crowded, etc). I don't think that most of us will run into a situation where we are running a train so long that the front and rear can't communicate. I know there are people who run 100+ car trains but normally that would occur on a Freemo-type setup, where there are almost no physical obstructions. Besides, Railpro is designed as a repeater system so there will be multiple pathways for any signal to get communicated.
-Kevin