Quote:
Originally Posted by stvcmty
That being said, 122 – 36 = 86 which is almost 90. So you are pretty close to the situation where just combining two antennas with a splitter reversed is most likely to possibly work. If two antennas with deep nulls 90 degrees off axis are pointed perpendicularly and then combined, on paper, they should not be picking up signals that will interfere with each other. (The non-committal language is because this is an experiment at your own risk suggestion).
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I think this is the best strategy. The overall method is to re-aim your ANT751 to 126degT so that the null is at 36degT (the direction you want to add).
IF you can get good signals from 122degT while aimed at 126degT then you can add the second antenna. If moving the antenna offline loses you critical stations then you'd have to try a different approach or modify the ANT751 for better reception. The number one mod would be to make a twin-lead extension so the balun drops away from the boom as quickly as possible. More details here
http://forum.tvfool.com/showpost.php...1&postcount=48
I found that it really increased my signal strength across all channels.
I noticed that you are picking up RCH2, RCH4 and RCH6 from 122degT and aiming at 126degT might knock these stations out. However, the ANT751 is optimized for VHF-Hi with the two 16" elements at the rear of the antenna. These elements should be at least 33" per side to pickup RCH6 so you'd have to extend them pretty far optimize them for VHF-Lo but you probably don't need to go that far and try extending them 12" to buy you enough VHF-Lo gain (and so you don't lose RCH12) that everything works with the antenna aimed at 126defT. Unfortunately this might make FM interference a problem so check your FM Fool report and make sure you don't have any high power FM stations around.
So now that you have the ANT751 aimed at 126degT (so its null is at 36degT) and you have retained all the critical stations you want you can add in a second antenna. (You did say you were a DIY'er, right?)
I would install a DB4 type antenna aimed at 36degT. Hopefully you won't need an amp as that would make multipath worse but the signals should be strong enough from this direction. I would setup and test the second antenna independently of the ANT751 before combining and make sure you get RCH9, RCH39, RCH46 in a reliable signal and strength. If the DB4 does not have enough VHF-Hi gain to pickup RCH9 you could add VHF elements to this antenna as described here;
http://forum.tvfool.com/showpost.php...45&postcount=8
Once everything is tested you can then combine the antennas using a standard (low loss) two-way splitter. Connect the antennas, re-zero your tuner and then rescan for channels and see what you get. Test it without an amp but if you have one put it right after the antennas are combined at the splitter. Another thing you might do is rerun your TV Fool report and raise the elevation and see if that improves any of these signals, especially if your PATH column goes from 2Edge to 1Edge or 1Edge to LOS and the elevation is not too great consider a taller mast for one or both installations.
Caveat: This might not work.