Attics and the inside of buildings Are Not a reception environment and Never Will Be a reception friendly environment.
Multi-path reflections signals bouncing all around , absorbing , blocking , Broadcast Tv reception.
Install a ANT751 antenna in the attic aimed at about 112 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
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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.
For 3 Tv's connected use a simple common 3 way splitter.
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If reception issues happen that are not resolvable with antenna aim and location in the attic.
Move the ANT751 antenna to above the Peak Of The Roof in such a manner that reception is not impeded or blocked by the roof and building in All directions.
Above the roof , aim the ANT751 at about 112 degree magnetic compass direction.
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