With one of the indoor type antennas out on the patio , should be receiving more channels then one channel. The Tv MUST SCAN for the Digital Broadcast Tv Channels sometimes named the 'Antenna Channels' or 'Air Channels' in the Tv setup menu because the Tv transmissions travel through the air from the transmitting antenna to the receiving antenna. DO NOT scan for cable Tv channels. Also the antenna must be connected to the antenna input connection on the Tv. Also amplified antennas Must be plugged in to work. Here is a Tv antenna that is made to look like a small dish.
http://www.antennacraft.net?Antennas...Amplified.html .
http://www.antennacraft.net/Manuals/HDX1000_manual.pdf . The antenna should be mounted up as high as possible on the outside of the building to receive the Tv stations to the north/west and south/east. Think about where the Tv stations are at , think in terms of getting the antenna to clear the roof. Here are some places to buy antennas and etc. ,
http://www.solidsignal.com ,
http://www.amazon.com . The make of the Tv is Sharp , what is the model number??