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Old 21-Aug-2015, 10:55 PM   #22
rabbit73
Retired A/V Tech
 
Join Date: Aug 2012
Location: S.E. VA
Posts: 2,518
Quote:
There's NO WAY I can get my antennas above them.
Understood. Then what you are left with is small increments of improvement like modifications to your yagi that I see on DHC and clearing the roof.

Stupid question: could a CH 12 antenna be mounted in a tree?

If your CH 12 yagi uses a balun, would reducing the balun loss help? When I was doing a mod on a 4-bay antenna for CH 15, I tried about 20 different baluns and found the difference between the best and the worst was about 5 dB. They were all ferrite core baluns, but I could have made a half-wave coaxial balun with even lower loss.

Have you tried looking at the green signal lines in a satellite view of your location. I was able to make good suggestions to mulliganman for the location of his C2V so that it would clear his neighbor's roof.







Quote:
The antenna actually aims at a bearing that's in front of the peak, but I still think the roof height might be problematical.
Kevin couldn't get the signals he wanted through the trees with his antenna aimed at the correct azimuth as you see in this photo. But when he aimed the antenna to the left where he is looking, he received some signals that came around the trees by diffraction.



http://www.avsforum.com/forum/25-hdt...l#post17280909
Quote:
We tried clocking the antenna at as many discrete positions as we had time for, with the rapidly fading light last night. We let Media Center run through the signal strength loop each time we moved the antenna. The best overall reception seemed to be pointing at the only real open spot out of my neighborhood, or about 300. As a refresher I was expecting to receive the strong RI stations @ 41 and the weaker Boston stations at 28-29 while pointed at ~32. Well, how about 300?
http://www.avsforum.com/forum/25-hdt...l#post17297708
Quote:
Cut down two trees and aggressively limbed the big white pine. I played the aim-game again with the laptop on the roof. I ended up at about 50 degrees which is almost exactly where the old antenna was aimed. Seems like the best overall trade off. I get a Boston CBS, ABC and FOX. And I get the off axis RI CW and RI ION. Boston 38 is intermittent but all of this is better than the 300 degree aim I said I was using earlier.
Attached Images
File Type: jpg Location 3-45deg.jpg (94.7 KB, 913 views)
File Type: jpg Location 4-45deg.jpg (77.2 KB, 950 views)
File Type: jpg Location 4-90deg.jpg (102.5 KB, 958 views)
File Type: jpg kevm14 on roof2.jpg (184.0 KB, 921 views)
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Last edited by rabbit73; 22-Aug-2015 at 12:15 AM.
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