Help please - RF modulator doesn't work

[Muncher]

So I went and bought an RF modulator at Factory direct (no refund they told me) for $14.99.

I connected the TV antenna into the RF mod. Then I connected the RF mod to the TV with (duh) the coaxial cable. Without plugging the RF mod into any power source, I can now watch TV as normal.

Then I connect the 3 red, yellow and white cables from the DVD player to the RF mod. Then I plug the power into the RF mod. Then I switch the power on on my DVD player, I set the TV to channel 3 using my TV remote, I set the channel on the RF mod to channel 3.

And voila, nothing happens! The TV continues showing the cable channels, and the light on the RF mod does not go on as it says in the manual.

The picture also shows a S-video cable between the DVD and the RF mod. Do I need this cable in ADDITION to the red/yellow/white one? I only have a coaxial input to my TV, nothing else.

Any suggestions would be appreciated as I really really want to watch some DVDs and I can't get my money back on the RF mod from Factory Direct.

[Gee]

You do not need to use the S-Video, the Yellow is composite video and is used for the video. The Red is the right speaker and the white is the left speaker.

If the unit is defective, take it back to Factory Direct for an exchange. They will not give you a refund, but you are entitled to an exchange.