Put the ANT111R antenna at/in the east window and run a coax from the ANT111R antenna to the Tv.
DO NOT connect to any cable/coax outlets in the apartment.
Aim the ANT111R antenna at about 99 degree magnetic compass direction.
Here is how to aim indoor and outdoor antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Digital Tuners can develop - Digital Glitches - that are not cleared out with a simple channel rescan.
I recommend do a Double Channel Rescan.
http://www.dtv.gov/rescan.html.
You can also put the ANT111R antenna out on the balcony and test reception.
DO NOT connect to any cable/coax outlets.
Connect a coax to the ANT111R antenna and run the coax direct to the Tv.