> How about a technique like that used in diversity reception. Put a
> dedicated receiver on each beverage and use (something? AGC?) to
> automatically select the strongest output. With manual override...
I use that method where the antennas are spaced more than one or
two waves apart.
I have a master receiver that supplies phase-locked oscillators to
secondary receivers, and the output can be combined in mono or
listened-to in stereo.
If anyone wants to post something on a Web page, I have stereo
recordings of DX signals. If you listen to them in stereo, you can
here the fading difference. If you look at it on a dual channel scope,
you can see the phase rapidly change. It is that rapid random
phase shift that makes it impossible to use physically large
antennas (more than 1or so wl in area) on 160 meters (and above I
suspect). If there wasn't a problem with phase, I would have some
really big antennas!
I commonly use my Europe verticals (four element 70ft endfire x
330ft broadside) against my Europe Beverages ( 800 ft endfire x
four elements spaced 350 ft broadside each) that way, since they
are separated by 5-6 wavelengths. I also use my phased Beverage
arrays (groups of two 800 ft elements spaced 350 ft broadside
running in six directions) against my circular (350 ft diameter eight
element) array in diversity because they are spaced 2-4
wavelengths apart.
If the array has close spacing (s <1.5 wl) you are almost certainly
better off to directly combine them at RF. That's what I used to do
when my system was less "spread out".
The wider the separation, the larger the effect. The less coherent
the noise becomes, and signal fades at a totally different time in
each ear.
You won't gain anything with antennas pointed in separate
directions except to fill in the pattern and make the pattern appear
wider. That generally costs some S/N ratio.
73, Tom W8JI
w8ji@contesting.com
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