For my turntable tracks, I used dtdp (double throw, double pole) switches. These switches have an up, down and center position. Up powers one track, down powers a second track and the center is off for both tracks. I only need one turntable track on at a time, the one where the engine is going to/from. No need for complicated electronics. So to power 8 tracks, I use four of these switches.
Switches, terminal strips and DC drive for the atlas turntable:
Wire connection schematic that is on the back of the panel, so I can see where all the wires should go. I then label all the wires, so they end up in the right place. I use colours that match the wire colours that I plan on using. In this case, all of the wires are either red for track power and black for ground.
The front of the panel, with 8 powered tracks, and one switch to turn the Atlas turntable clockwise, counter clockwise, or off (center position of the switch)
Design schematic for the wiring. I did this using an Excel spreadsheet, sizing things correctly for the size of the switches and terminal strips. It may take a few tries to get the sizing right. This allows you to have clear label names, so the wires get connected to the right place.
The labels on the front show the track number (T!, etc) inside a CP logo. You can do the same using a version of the logo for any railroad. The same label is then on the track, so you can easily see the number of each track. Using the railroad logo makes it look better on the layout.
However the electronic LED idea is cool and would work well.
