daveb:
Holy Moley, Batman! KISS, anyone?
My twin-coils are operated off a dedicated power supply with enough capacity to eliminate any fancy electronics (38 watts at the source) and my indicators are wired to the contacts on the switch machines (ancient KTM, 3PDT, and more recent RIX, DPDT) without any connection between the two. Machines are operated by either a hot probe or a rotary switch circuit that CAN'T keep one coil powered until it smokes.
If I was a Tortoise user, there are circuits that allow the use of a single SPDT toggle per machine, and LEDs can be wired in series with the power to the Tortoise to indicate direction.
For the price of one super-switch, I can wire an entire control panel for a twelve track single-ended staging yard. In fact, I already have.
Chuck (Modeling Central Japan in September, 1964 - as inexpensively as possible)