Thank you for being honest about your reception situation.
Looking at the Current+Pending Applications Included Digital Broadcast Tv stations/channels to the north west , are showing as LOS =Line Of Sight and strong signal strength , except for one , WPXJ-DT Uhf channel 23 ION is showing moderate signal strength and 1 edge path obstruction.
The trees and obstructing building will be the situation/problem with reception.
Recommend install a Winegard HD7698P antenna above the Peak of the Roof in such a manner that roof and house are not blocking reception to the north west.
Aim the HD7698P antenna at about 300 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
As always the starting antenna aim direction is the -->starting antenna aim direction.
The antenna aim direction and antenna height above ground can be adjusted for best reception.
Most digital Tv's have a signal strength meter and some Digital Tv's have a signal quality meter.
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Here are some strong and sturdy antenna mounts.
http://www.ronard.com/909911.html. Use the 5 foot tripod antenna mount.
http://www.ronard.com/Tripods%200703/4712.html.
http://www.ronard.com/34424560.html. Use the #4560 eave antenna mount.
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.
Here are some places to buy antennas and etc. .
http://www.solidsignal.com.
http://www.amazon.com.
http://www.winegarddirect.com.
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A antenna system amplifier will most likely not be required.
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For 1 Tv connected use no splitter.
For 2 Tv's connected use a simple common 2 way splitter.
For 3 Tv's connected use a simple common 3 way splitter.
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The situation/problem at your location is the trees and other obstructions.
Trees and tree leave , plants and plant leaves , have a negative effect , multi-path/reflections , absorbing , blocking , Tv reception and so do buildings including your own roof and house and other obstructions.
The Best Practice is to install the HD7698P antenna at a location that has the least amount to no amount of 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 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.