I have a F12 C3 at 79 feet and a Cushcraft 40-2CD above if at 90 ft. There
was quite a bit of interaction with the C3. Could not get the SWR to come
around so I had to rotate the 40 90 degrees. This made all the difference
in the world.
I can't recall what Tom suggests in the Array of Light book. I do recall
having some conversations with him about it. I think the 40 ended up on top
to get it as high as possible.
In the past I have had a wide spaced 15 meter yagi and a full size 2 ele 40
meter beam on the same tower with spacing. The 15 was on top in this setup
and I don't recall having any interaction at all. It seems to depend on the
physical design of the antennas.
I would suggest sending a note to Force12@qth.com and tell them what you
want to do and see what they say. Tom and Natan have been very helpful.
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