The following is a Teleview recommendation for Digital Broadcast Tv Reception.
A Simple reception situation for reception of the group of broadcast Tv stations/channels to the south , 180 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Above the roof install a Winegard HD7698P antenna with no preamplifier aimed at about 180 degree magnetic compass direction.
For 1 Tv connected use no splitter.
For 2 Tv's connected use a common simple 2 way splitter.
For 3 or 4 Tv's connected use a Channel Master CM3414 distribution amplifier.
Here are some above the roof antenna mounts ,
http://www.ronard.com/909911.html ,
http://www.ronard.com/34424560.html ,
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.
Here are someplaces to buy antennas and etc. ,
http://www.solidsignal.com ,
http://www.amazon.com ,
http://www.winegarddirect.com ,
http://www.channelmasterstore.com.
As always , trees and tree leaves do a real fine job of reducing or blocking Tv reception and so do buildings and other obstructions.
It is best to install the antenna at a location that has the least amount to no amount of obstructions of any type or kind in the direction of reception.
DO NOT channel scan for cable tv channels.