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A question on the practicalities of aiming the antenna:
As a first pass trial of reception, I would plan to aim the antenna from my roof (single story house). How specific is my goal in the degree aiming... +/- 5-10 degrees?
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Interesting question. There is the straight forward practical part, that concerns signal strength. How critical the aim depends upon the horizontal beamwidth of the antenna that is given in terms of the halfpower (3 dB down, or 0.707 voltage) points (HPBW). Generally, the higher the gain, the narrower the beamwidth, which is an inherent trade-off, because energy cannot be created or destroyed, only converted. Or, as ADTech likes to say
TINSTAAFL
http://www.antenna-theory.com/basics/radPatDefs.php
http://www.cisco.com/c/en/us/support...vs-direct.html
Looking at the beamwidth charts for the 7698, I see different answers, but think the chart at solid signal is wrong:
http://www.solidsignal.com/pview.asp?p=hd7698p
Click on specifications, and scroll down to the chart below Step 3
And also wrong here:
http://www.winegarddirect.com/viewit...HD7698P)&post=
The correct Winegard chart is here:
http://www.winegard.com/kbase/uploads/HD7698P.pdf
The more esoteric part concerns signal quality. I have found that if I make the initial aim based on signal strength, and then monitor signal quality based on SNR and errors, I am able to optimize aim. The greatest signal strength and the best signal quality aren't always at the same azimuth. Go for signal quality. My Sony TV has a diagnostics screen that gives signal strength, SNR, and errors.
You can use the green signal lines from the tvfool interactive map feature to help you aim. You can move the teardrop cursor to the exact antenna location. Then pick a landmark.
Please tell us how it works out. We need the feedback to know if our advice was accurate.