http://www.amazon.com/Cisco-Linksys-High-Antenna-Connectors-HGA7T/dp/B0002F3G7M is a great place to get the latest high gain antenna with great prices.

Italian Space Agency provided the High Gain Antenna for the Cassini Space Probe.

The HGA was built by Alenia Aerospazio.

A high-gain antenna is an antenna which allows for precise targeting of radio signals due to it's use of a narrow radio wave beam. To use a high-gain antenna you should put attach it to a high, clear surface to allow it maximum range to receive and send radio signals. A good place would be the roof of your house.

You can buy high gain antenna's for your task at a number of online shopping sites, such as amazon.com. I would suggest going there to fulfill all of your needs.

There is a website called Antennahub.com that sells them. You may also want to check the place you brought your TV from. They will be able to tell you if you do need a high gain antenna and what will work with that TV