In/at a window that is toward the , south - south west , put a Terk HDTVi antenna aimed at about 206 degree magnetic compass direction.
Here is how to aim indoor and outdoor antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Run a coax from the HDTVi antenna to the Tv.
Digital Tv Tuners can develop - Digital Glitches - that a simple channel scan does not clear out.
Do a Double Channel Rescan.
http://www.dtv.gov/rescan.html.