what you should do before you get into the illegal stuff is call your cable company and have them get all your existing cableing up to spec... ie fix the screw on connectors properly ground everything, etc. They should do this for free if you just say you are getting really crappy reception. You can also probably get an amplifier that will allow a cable model signal through from them this way. Just keep complaining and ask if they will put an amp on. You should only need on amplifier depending on the quality of the cable that is run through your house. If you are running all this yourself, make sure you get shielded RG6 cable.