Above the roof install a ANT751 antenna aimed at about 174 degree magnetic compass direction.
Toward channel 8.
http://www.solidsignal.com , has the ANT751 antenna with a J type antenna mount , low dollars.
The ANT751 does have some forward gain for improved reception of channel 8.
The ANT751 is not a very directional antenna and Will receive the stronger Digital Tv stations/channels to the north west and east.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
For 1 Tv connected use no splitter. No antenna amplifier.
For 2 Tv's connected use a common simple 2 way splitter. No antenna amplifier.
For 3 Tv's connected use a common simple 3 way splitter. No antenna amplifier.
As always , trees and tree leaves do a real fine job of reducing or blocking Tv reception and so do buildings and other obstructions including your own house.
It is best to install a antenna at a location that has the least amount to no amount of obstructions of any type or kind in the directions of reception.
The Tv/s Must Channel Scan for the Digital Broadcast Tv Channels , sometimes 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.
DO NOT channel scan for cable tv channels.