Ok , I recommend antenna height of no less then 40 feet above ground and closer to 60 feet above ground is better.
The reference point is WNYA-DT REAL VHF Digital channel 13 , virtual number (51.1) MyNetwork.
At 25 feet the NM(dB) signal strength is Minus -10.2 . Not good , however might provide reliable reception.
At 40 feet the NM(dB) signal strength is Minus -5.7 . A little better and will most likely provide reliable reception.
At 60 feet the NM(dB) signal strength is Plus 3.1 , better.
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WRNN UHF channel 48 Regional News Network and Multi cultural programing.
WTBY UHF channel 27 TBN.
Are Strong signal strengths and will be received through the back of the antenna.
And W30AZ UHF channel 30 Spanish language , will most likely be received at the back angle of the antenna.
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I recommend the Winegard HD7084P antenna with a Antennas Direct CPA-19 preamp , aimed at about 8 degree magnetic compass direction.
Here is how to aim antennas ,
http://www.kyes.com/antenna/pointing/pointing.html.
As always , the starting aim direction of a antenna is the --> starting aim direction of a antenna.
-->If required<--The antenna aim can be change and the antenna can be moved up and down or relocated to find the best reception.
Most Digital Tv's have a signal strength meter and some Digital Tv's also have a signal quality meter.
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Here are some Strong and Sturdy antenna mounts ,
http://www.ronard.com/909911.html ,
http://www.ronard.com/Tripods%200703/4712.html ,
http://www.ronard.com/34424560.html ,
http://www.ronard.com/ychim.html.
Buy the ronard antenna mounts at solidsignal by typing the word ronard in the solidsignal search box or buy from ronard.
Here is a , free standing no guy wires , light weight aluminum , lay over tower , do all antenna install and adjustments standing on the ground.
http://www.palcoelectronics.com/pe300.aspx.
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For 1 Tv connected use no splitter.
For 2 Tv's connected use a , HFS-2D , 2 way splitter.
For 3 Tv's connected use a , HFS-3D , 3 way splitter.
For 4 Tv's connected use a , HFS-4D , 4 way splitter.
Buy the HFS splitters at ,
http://www.solidsignal.com or
http://www.hollandelectronics.com.
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As a test of reception of the Weak Digital Tv stations/channels to the , south - south west.
Aim the HD7084P antenna with the CPA-19 preamp at about 200 degree magnetic compass direction.
Scan for channels and see what is received.
Digital tuners can develop - Digital Glitches - I recommend doing Double Channel scans.
http://www.dtv.gov/rescan.html.
http://transition.fcc.gov/cgb/consumerfacts/rescan.pdf.
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As always , trees and tree leaves do a real fine job of reducing or blocking Digital Broadcast Tv reception and so do buildings and other obstructions including your own house.
It is best to install the antenna at a location that has the least amount to no amount of obstructions of any type or kind in the directions of reception including your own house.
The Digital Tv/s Must Channel Scan for the Broadcast Tv Channels , often named the 'Air Channels' or 'Antenna Channels' in the Tv setup menu because the Broadcast Tv transmissions travel through the air from the transmitting antenna to the receiving antenna.
DO NOT channel scan for cable tv channels.