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Old 11-Mar-2018, 7:29 PM   #20
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,545
mars1162

Thank you for the coordinates by PM. My guess was only 150 feet away, so the profile is similar.
Quote:
I am showing ground elevation at my antenna to be 493 feet and with antenna on a 40 foot pipe that would be roughly 533 feet above sea level.
The elevations from 3 sources for your location were 430, 433, and 433 feet, so I'm wondering where you got 493.



Quote:
Originally Posted by mars1162
One of my goals I was trying to find a antenna that get the best possible signal on weaker stations with strong stations nearby.
That will not be easy, because there is a great difference in signal strength between the strongest and the weakest. Preamps and tuners have a limited range of what they can handle.

Your report for reference:
http://www.tvfool.com/?option=com_wr...9038b9ec20c134




Your FM signal report
http://www.fmfool.com/modeling/tmp/d...9/Radar-FM.png

The difference between your strongest signal and your weakest desired signal is call the Signal Dynamic Range. In your case, it is the difference between WTVW with a signal power of -2.2 dBm and WVUT with a signal power of -89.9 dBm, which is 87.7dB. To that, you must add the minimum required SNR of 15 dB for WVUT, giving a required SFDR (Spurious Free Dynamic Range) of 102.7 dB.



There are no preamps that have that kind of SFDR. The closest readily available preamp is the Antennas Direct Juice with a SFDR of 81.7 dB and a maximum signal input of -21.3 dBm, both of which are exceeded by the signals on your TVFool and FM Fool reports. The only thing that helps is when your antenna is aimed at WVUT, the strong signals in other directions are made weaker by the antenna pattern.



You will probably need a preamp because of your long coax feedline (how long is it?), but you might need to add an FM filter and an attenuator between the antenna and the preamp to keep it from being overloaded.
Attached Images
File Type: jpg mars1162TVFp2WVUTrev.JPG (110.5 KB, 937 views)
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Last edited by rabbit73; 12-Mar-2018 at 1:32 AM.
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