Many laptops have an SVIDEO jack for TV-Out, so the adapter can be problematic. There are two types of svideo->rca adapters, so ensure you have one that is made for svideo->composite out, versus a composite-in (for capture) to svideo.
Once you ensure you have the correct adapter and have the cable properly hooked up to a TV or video-in source, you may need to reboot the laptop or restart windows as some drivers will not enable TV-Out unless they detect the svideo/composite cable is connected to a live source.
Once this can be established, you'll need to consult the documentation for your video drivers. Most laptops have output source selection in either a systray application (bottom right-hand side of the desktop where the time/clock shows) or you may have to go into Advanced Display Properties. You can get to the Advanced Display Properties by right-clicking on your desktop in an open space (not on any icons), select "Properties"... in the Display Properties, go to the last tab on the top/right labeled "Settings" and hit the "Advanced" button near the bottom.
If you provide more system information, more precise instructions can be given. The above information captures most laptops/tv-out drivers and settings but there are just so many different manufacturers and drivers that it is impossible to give perfect information with no system information at all. Hopefully your laptop is covered above, but if not, please reply with the full system information for your laptop. Make, model, etc.etc.
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