As always trees and tree leaves do a real fine job of reducing or blocking Tv reception and so do buildings and other obstructions including your own house.
It is best to install the antenna at a location that has the least amount to no amount of obstructions of any type or kind in the directions of reception.
Here are some but not all above the roof 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.
http://www.solidsignal.com.
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