Because of the close , less then 4 miles and Very Strong signals , a amplifier is not recommended.
A amplifier will most likely overload and be the cause of bad reception.
Attics and crawl spaces Are Not a reception friendly environment and Never Will Be a reception friendly environment , signal attenuation and signal reflections (multipath) are not good for reception.
Above the roof in such a manner that the roof and house does not block reception to the , south east.
Install a Winegard HD7696P antenna aimed at about 145 degree magnetic compass direction, here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
For 1 Tv connected use No splitter. No amplifier.
For 2 Tv's connected use a simple common 2 way splitter. No amplifier.
For 3 Tv's connected use a simple common 3 way splitter. No amplifier.
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Here are some above the roof antenna mounts.
http://www.ronard.com/909911.html , if using the tripod antenna mount use the 5 foot antenna mount.
http://www.ronard.com/34424560.html , if using the eave antenna mount use the #4560.
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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As always , trees and tree leaves - plants and plant leaves , do a good job of , reflecting , reducing , blocking , Digital Tv reception and so do buildings and other obstructions including the roof and house.
It is best to install the HD7696P 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 the roof and house.