Thanks all. If it had required a great degree of electronics knowledge, I wouldn't have been able to do it

The whole project actually started when one failed outside the warranty period. Screwed around and was able to figure out the transmitter board was the problem, so I contacted the vendor hoping to get just a replacement board (no luck). But, in further discussion he told me about them being able to run off 12v power and the ideas just kinda developed from there. Take care, and happy Memorial Day to everyone.