The idea of hooking the lights and radio up to a motion detector sounds like a great one. That way the critters would be less likely to get used to the sounds and ignore them, hopefully.
I had a raccoon come down my chimney (which is now capped!!) a few years ago, and she gave birth to her babies there. When I called Colorado Fish & Game, they told me studies said I should try a radio. When I asked which station they preferred, he just laughed. (This was all after he first recommended that I just run out and get myself some fox urine.)
I've always wondered how much of my tax dollar funded the study.
Put it right outside your coop, cause then if it scratches the radio, the coon could get electricuted and die... Problem solved. Can't you just keep it on your favorite station?