Hi,
I have never seen a S-Video in on a vcr or dvd player , both of my dvd players and vcr have S-Video out . I have my S-Video from my geforce running into the RF modulator out into the vcr via coax cable with my two dvd players hooked into the vcr via rca jacks , then out from the vcr to two tvs a regular 27 inch tv and a flatscreen 27 inch so I can record gameplay, satalite (direct tv) , movies , dvds movies, and just about anything eles I would want to record on a vcr tape . The reason for two dvds is one has surround sound 5.1 with speakers . and the other one supports all video formats Svcd Vcd Mpeg and so on plus also has dolby 5.1 (Was only $30 for that one at sears) and on top of that I have my pc audio running into the surround as well so im totally hooked up here. sounds like you need a Rf modulator, but I could be wrong if your vcr or dvd is S-Video in. So basicly I can surf the net , watch tv and play a game all at the same time , oh and did I mention I have a tv tuner also lol.