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Old 11-Dec-2016, 9:10 PM   #4
Retired A/V Tech
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,545
Originally Posted by davodavo View Post
I put in my street address, but something is messed with the altitude calculation because the results assume I can see through big hills that put me in the signal-shadows.
A terrain profile will show the direct path from the transmitting antenna, but some TV signals can make it to your antenna by atmospheric refraction which bends the signal down to your antenna and diffraction as it encounters the peak of a hill. VHF signals are more common in rough terrain because they can make it over terrain obstructions more easily than UHF signals. The tvfool simulation takes some of that into consideration, but its accuracy with 1Edge and 2Edge signals isn't as good as for LOS signals. The report assumes your antenna is outside and in the clear with no trees or buildings in the path.

Your report says your antenna is only 10 feet AGL; is that true?

If you click on a callsign in your report, you will see a terrain profile:


Here is a terrain profile for KNTV using different software. Note the curvature of the earth makes reception more difficult.

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File Type: jpg davodavoTVFp2KNTV.JPG (111.3 KB, 2144 views)
If you can not measure it, you can not improve it.
Lord Kelvin, 1883

Last edited by rabbit73; 11-Dec-2016 at 11:14 PM.
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