I have started constructing railroad signals for the signal system that I will install into the layout. This system will be fully functional and will operate under aspects that I have devised based off of real railroads signals manuals. I have come up with a manual of my own that I will post onto my site then link to here once I have revised it. So far I have a couple searchlights, a bi-directional three light, and another three-light that I purchased last night. This three light was a Model Power that came with incandescent bulbs, I replaced these with LEDs.
Here is a couple of video links of the bi-directional signal in a demostration.
http://www.youtube.com/watch?v=n-h88qtTsCE http://www.youtube.com/watch?v=bXz9eefnTkY