So lets start wiring Main 1 (blue) for a block signal. We need two circuit boards in order to set up this block. The first is the brown Chubb DCCOD detector on the right. The second is the purple Modutrak signal driver board. These signal drivers are patterned after the TracTronics signal driver boards, which can also be used, but we've added a microprocessor in order to mimic the bouncing mechanism in a searchlight signal mechanism. More on that later, but for the time being we'll look at how these signal driver boards are wired. Also appearing in this diagram is the Cat5 cable whose brown and brown/white wires are broken out at this block.