I'm trying to get block detection working on my HO scale model railroad. I found this page and liked the idea of using current transformers to detect the Digital Command Control signal inducing ...

OK. A bit more reading and head scratching.... let's see if I have this right. Resistor values chosen for 0.5mA current flow. DCCOD > Arduino one. Tie the 12VDC and 5VDC power supply grounds together, ...