It will be helpful if the HD7082P antenna can be mounted higher then 15 feet , say 25 feet. Try the HD7082P at 15 feet if you get reliable reception then Ok. If not then go higher , Here are some different mounts , chimney mount CM9067Y -
http://www.eham.net/libraries/download/430/Photo_A.jpg note that the straps are far apart this makes the antenna more stable. Next is tri pod mount -
http://www.antennacraft.net/Manuals/10Y203_manual_.pdf . Next is a eave mount -
http://www.sadoun.com/Sat/Products/Perfect/PVEM1.gif