Your past posts say that you have a Antennacraft HBU33. The information I am giving is for the Antennacraft HBU33. NOT the Philips. Read and understand this about Real Digital Tv Channels and Virtual Digital Tv Channels.
http://forum.tvfool.com/showthread.php?t=695 The Tv stations to receive are in the direction of 314 magnetic compass reading , the Tv antenna needs to be pointed in that direction and because the Tv stations are weak the Tv antenna needs to be Up High and clear of being blocked by the roof. In other words , the roof of the house must not be blocking reception. Tv antennas receive the best when nothing is blocking reception. Mount the Tv antenna at the top of the roof. Also the HBU33 Tv antenna must be horizontal with the ground. If you do not know what that means then think about this , when you lay on the ground you are horizontal with the ground , when you stand up you are vertical with the ground. Is more then one Tv is connected to the antenna?? If So. How many Tv's are connected?? <-- . --> Are the Tv's connected with coax cable ?? <-- . --> With a passive splitter or a amplified splitter ??<--.--> Is a preamplifier connected to the antenna ?? This is how to point a Tv antenna
http://www.kyes.com/antenna/pointing/pointing.html You will find the bulk of the Digital Television Channels to the North West.