We have designed a layout at my place with double main line with reverse loop at each end.
Plus there is a branch line with two reverse loops that in one loop is connected to the main line.
The main lines stay double track even at the split.
The branch stays single with only one connection with the main.
My plans where to use the AR1 for all my reverse loops and the PM42 for my power control.
What if any problems do you see with all these loops?
Nothing, if you can guarantee that at any given time only one train will be in any of the four (by our count) reverse loops that you will have on this railroad.
Simply, you must have one AR1 for each reversing segment.
The voltage present in the DCC environment is AC instead of DC.
It is the mobile decoder which converts the AC current with DCC signal into DC for the locomotive's motor.
The AR1 and, also the PM42, compares the track voltage phase of the main line and the reverse loop section.
When a locomotive passes from one segment to the other, the AR1 (or one node of the PM42), compares the DCC signal and adjusts the reverse loop segment to match the DCC signal of the main line.
Since there is the possibility of having more than one locomotive simultaneously passing from a reverse loop segment back into a main line segment, you must have an AR1 for each reversing segment.
Because the four nodes of the PM42 are isolated from each other, one PM42 could be used, with each of the nodes controlling an individual reversing section.