I believe the RF Modulator that dguns is referring to is the exact one that I use. The link below will take you to the CRF940 RF Modulator built by RCA. It has worked perfectly for my laptop w/s-video out and multiple TV's. It allows for RCA, Coax, and S-Video connections.
Here's the Link
http://www.bestbuy.com/site/olspage....1&type=product
Just click on view more photos and it will give you front and back views of the product.
hope this helps
Flipper