NTSC is the Old Analog Broadcast Tv standard.
-->ATSC<-- is the New Digital Broadcast Tv Standard.
Here is the owners manual , http://store.vizio.com/documents/dow...L32/Manual.pdf
I see on page 26 that there are 2 antenna inputs , 1 for Analog and 1 for Digital.
The one for Digital is the 1 that the antenna is connected to.
I see explainations on pages , 30 and the next pages for scanning for Digital Broadcast Tv Channels.
The Digital Broadcast Tv Channels are the ATSC Channels.
DO NOT channel scan for NTSC channels.
Put the indoor type antenna , in/at a window , patio/balcony , that faces , south east as a 1st. choice.
East as a 2nd. choice.
South as a 3rd. choice.
If required , use a loooong coax so that the antenna can be in/at the window / patio/balcony window.
Aim the Mohu Cheap or the VN1ANTP1 , at about 130 degree magnetic compass direction.
Here is how to aim indoor type antenna and outdoor type antennas , http://www.kyes.com/antenna/pointing/pointing.html
So is this a , house , town home , condo , apartment , mobile home , motor home , or etc.??
What directions do the , windows , patios/balconies , face.
What is the top floor??
The type of building construction that is the best for indoor antenna reception is , wood with wood of vinyl siding.
The following is a - Non complete list - of building construction that Will , reduce and block Tv reception.
Concrete , concrete blocks , concrete tile roof , bricks , big rocks , metal siding , metal roof , metal beams , metal backed insulation , stucko Wire , and more.