Hi,
I was asked about rf modulators with a pvr350 and figured if one person had questions, may be there were two or more with a simular question. He said that I said Kmart.... appologies if so.
I thought I had said Walmart...~$25, anyway a RF modulator is a mini tv transmitter that you plug your composite video and stereo audio into where it is "modulated" on to a Radio Frequency carrier for a regular tv to receive on channel 3 or 4. (USA NTSC) An example is a vcr or dvd player that has "RF out"
You may also purchase modulators other channels from special vendors as they are often used for "in-house antenna" systems. You may also purchase a special filter that would allow you to have your regular cable / antenna signals, channel 7 and up to pass normally and the channels 6 and under signal to also pass normally to the one tv system. You would loose the low channels for direct viewing however a split before the filter you could still record them for later viewing.
All smoke & mirrors
Mike