The Tv transmissions at your location are Very Strong and Many channels will be received.
If the house is wood frame with wood or vinyl siding , standard non metal backed insulation , composition shingles.
Then install a Terk HDTVi (not HDTVa) antenna at each Tv location.
Aim the HDTVi antenna at about 260 degree magnetic compass direction.
Here is how to aim indoor antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
If the house has , metal siding , metal backed insulation , concrete walls , concrete blocks , cinder blocks , bricks from ground to roof , big rocks for walls , metal roof , solar panels , indoor Tv antenna reception will be reduced or blocked.
If the downstairs Tv is actually in the basement then reception will not be good in the basement with a indoor antenna.
The Tv's Must Channel Scan for the Digital Broadcast Tv Channels , sometimes named the 'Air Channels' or 'Antenna Channels' in the Tv setup menu because the Tv transmission travel through the air from the transmitting antenna to the receiving antenna.
DO NOT channel scan for cable channels.
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