As always , attics and the inside of buildings Are Not a reception friendly environment and Never Will Be a reception friendly environment.
Multi-path reflections signals bouncing all around , absorbing , blocking , Broadcast Tv reception.
That said , the Digital Broadcast Tv stations/channels reception in the Green and Yellow reception zones are Strong Signal Strength at your location.
However the trees will reduce signal strength and cause multi-path reflections and the antenna in the attic does not help.
Even so , start with a Winegard HD7694P antenna in the attic.
Aim the HD7694P antenna at about 193 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
My Real recommendation is a Winegard HD7696P antenna , however Winegard has done the Stupid Move of discontinuing the HD7696P antenna.
It's a real head shaker and eye blinker of the stupidity , discontinuing the HD7696P.
If you can find a HD7696P antenna on the internet somewhere then use the HD7696P antenna.
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A antenna system amplifier is not required.
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For 1 Tv connected use No splitter.
For 2 Tv's connected use a simple common 2 way splitter.
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If there are reception issues that are not resolvable by adjusting antenna aim and location in the attic then move/install the , HD7696P / HD7694P , antenna to Above The Peak Of The Roof in such a manner that the roof and house are not impeding and blocking reception to the , south west , south , south east , east north.
Here are some above the roof antenna mounts.
http://www.ronard.com/909911.html. Use the 5 foot tripod antenna mount , ronard (911) .
http://www.ronard.com/34424560.html. Use the , ronard (4560) , eave antenna mount .
http://www.ronard.com/ychim.html. Measure the chimney and use a , ronard (2212) , ronard (2218) , ronard (2224) .
Buy the ronard antenna mounts at solidsignal by typing , ronard (x) , in the solidsignal search box or buy from ronard.
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Here are some places to buy antennas and etc. .
http://www.solidsignal.com.
http://www.amazon.com.
http://www.winegarddirect.com.
http://www.ronard.com.
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As always , trees and tree leaves , plants and plant leaves , have a Negative effect on Broadcast Tv reception with a Tv antenna , multi-path/reflections , absorbing , blocking , Broadcast Tv reception and so do buildings including your own roof and house and other obstructions.
The Best Practice is to install a antenna in such a manner that there little obstructions to no obstructions of any type or kind in the directions of reception including your own roof and house.
The Tv/s Must Channel Scan for the , OTA=Over The Air , Digital Broadcast Tv stations/channels , often named the 'Air Channels' or 'Antenna Channels' in the Tv Setup Menu because the Tv transmissions travel through the Air from the transmitting antenna to the receiving antenna.
Some Digital tv's will Automatic channel scan for cable tv channels.
DO NOT channel scan for cable tv channels.
Go into the Tv Setup Menu and select 'Air Channels ~ 'Antenna Channels'.
Scan for channels.