Quote:
Originally Posted by Maury Markowitz
In this case, two antennas in different directions, is it not the case that if one of them is 90 degrees off the other, the phasing issue will be eliminated because the output from the second will be zero?
But I still have the combiner loss too, right? And is that loss 3 db?
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With the 2 at 90 degrees you "might" get good results by taking advantage of what's called the null direction of the antennas. This works best on directional antennas with narrow beam widths. One antenna is aimed at the others null signal zone, so to speak.
And yes, combiner loss will still be there, usually slightly more than 3db as no combiner is 100% efficient.
I've tried this with 2 DB4's at 90 degrees apart and did not get any better results than a single DB4. These were DYI antennas so I may have other issues in the mix, but I was not impressed enough to continue with the project at this time. I haven't given up on it, but it's seems less likely to be of any improvement to my reception.
Forum member holl_ands did a computer simulation of a vertical DB8 with 90 degree separation, (basically 2 DB4's vertically stacked), and the computer model does show it should be possible to achieve multi direction reception. I used his model in my tests.