For the best reception I recomand a Winegard HD7000R antenna mounted above the roof is ok (does not need to be 25 feet above the ground) aimed at about 120 degree magnetic compass.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Here are some antenna mounts ,
http://www.ronard.com/909911.html ,
http://www.ronard.com/34424560.html ,
http://www.ronard.com/ychim.html ,
http://www.ronard.com.
Buy the ronard antenna mounts at solidsignal by typing the word ronard in the solidsignal search box or buy from ronard.
http://www.solidsignal.com ,
http://www.winegarddirect.com ,
http://www.amazon.com