Install the DB8 antenna above the peak of the roof in such a manner that the roof and building are not , obstructing , impeding , blocking , reception in the directions of , West , South West , South , South East , North , North East.
Aim the antenna at about 210 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
Use a Real and Actual magnetic compass to aim antenna.
Digital Broadcast Tv tuners can develop -Digital Glitches- that are not cleared out with simple channel scans.
Do Double Rescan ,
http://www.wchstv.com/DoubleReScanAlert.pdf.
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