The OTA= Over The Air , Digital Broadcast Tv transmissions are medium strong at your reception location.
Antenna height is important.
And - Antenna Location - is -->More Important<-- at your reception location.
As always , Trees and Tree Leaves do a good job of , Reflecting , Reducing , Blocking , digital broadcast Tv reception and so do buildings and other obstructions including your own roof and house.
Install the CS4 antenna at a location that has the least amount to no amount of obstructions of any type or kind in the direction of reception including your own roof and house.
The Chic ago Digital Tv stations are at about 41 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html