I have been working for the past two months on an extensive renovation project of my layout. Part of this work included retooling the switch yard where I store passenger trains not in service. Since 14 passenger trains present a tremendous power requirement were they all to be on an active track, I needed to come up with a way to power these tracks as wanted and at the same time limiting the power requirements.
Jim Williams (ibew701 on the Forum) based on my design requirements built a rotary dial control system to handle the power issue. You simply dial the desired track and it becomes active. All others stay inactive. I have a similar system that controls the 21 tracks in my roundhouse area. Incidentally Jim has does work under the name of Dream Layouts. He is a great friend and the system he built is really slick.
There are three components, the rotary controls, the relay board and a 12 volt DC power supply.