Monitor and TV problem?

OK, what I want to do is have my monitor extended onto my TV. But my TV doesn't have an SVIDEO port. But the video card (Gforce 7600gt) came with a svideo to RCA adapter. So I plugged that in to a RCA leading to the TV. Well the computer doesn't see the TV. So I put on Force TV detection. Still nothing. So I activated the TV for M/NTSC at 640X480 acting as my second moniter. Still....Nothing. Whats weird is the computer is acting like there are two moniters because I can drag the cursor and windows to where the second moniter should be. Any ideas on whats going on? I think it is sending out a signal but somthings not working right. Thanks

Monitor and TV problem?
make sure both the TV and computer are set to NTSC or PAL


also you may have to use both interlaced or deinterlaced (progressive scan)