Duelview with GeForce FX 5200, analog + TV; TV receiving no signal

I just purchased an s-video cable in order to use a Symphonic 20in LCD TV (WF20L6) in conjunction with a Sony CPD-100ES monitor (on the analog output) of my GeForce FX 5200. The NVIDIA software detected that I plugged in the s-video cable and that it's hooked up to my TV, yet it appears that the TV is not getting the signal.

UPDATE:

I did a bit more digging, and it looks like the TV is not being recognized as a device in my system. SiS Sandra reports that there is only the "Default Monitor" device (although it lists three of them, all identical), as well as my Sony CPD-100ES. So now my question might be, how do I get Windows to recognize my TV as a monitor?