What you need first is a modulator such as the E1200 or E4200, this converts your CCTV feed into an RF feed. The E1200 is a single channel modulator, the E4200 is a four channel modulator. If you have 2 coaxial cables running to each of your TV locations, you can use one for your digital cable and one for the modulated feed and you would not need to use a P-0321. The primary purpose of the P-0321 is if you only have one feed already being used to take digital cable to your TV. In this case you cannot combine the modulated feed with the digital cable feed. So the P-0321 acts as a switch, it will allow one feed to come through, or the other. You can use the remote and the IR receiver that comes with the kit to send the signal back to the P-0321 and tell it to let through one or the other, but never both at the same time. For more information on the product see the manual here.