Hi, I ran a search on this site and learned everything I could about RF Modulators, but I still have a problem. I recently bought a Yamaha home theater system and I'm running into a problem because my TV only has a co-axial input. So I got an RF Modulator from Best Buy and hooked everything up. The set-up has a Digital Cable box connected to a VCR. The VCR and DVD player are connected to the Receiver. The Receiver connects to the TV via the RF Modulator. Of course the set up is more complex because, for some reason, Yamaha's "Quick-Connect" instructions require you to set up all kinds of loops (e.g., VCR connects to the Receiver and then the Receiver connects back to the VCR). Now I'm noticing that I get these lines pulsating on my TV. It's not a fixed line. It's more like a flickering set of lines that fade in and out of the background. The lines only appear when I am using the system. If I turn everything off and just watch cable, the image is fine. I would appreciate it if someone could help me figure this out. Thanks, Shashi.