Nope. A single antenna is all most of you will ever need. Of course, for the smaller indoor antenna models, you can just add them as needed if you don't want to drag cable around the house. But with an outdoor antenna, you can share its signal with a coaxial splitter. That's a simple gadget that you hook up to your antenna's cable and then split, usually from two to eight, other cables that go to your TVs. Some of the best splitters are the GE 33526 cable splitter, which can only split the signal between two televisions, the four-way RG6 RG59, and the Neoteck 8-Way Coax Cable Splitter. You can buy the first two for under $10, and the Neoteck for under $20.If you have over four TVs, you might want to use an amplified cable splitter. My favorite is the $55 Channel Master TV Antenna Distribution Amplifier, TV Antenna Signal Booster.