In a message dated 97-12-05 09:16:45 EST, ve7im@mail.island.net writes:
> What is the bandwidth of this ant? It's a 37ft long rotatable dipole. It's
> made by F-12.We see only 30khz,and ant is up 60',stacked inline with boom
of
> a f-12 "DXer"(20-17-15m) Stacking distance is 2 1/2 ft.
Hi, Dave --
I usually see avout 70-100 kHz bandwidth (between 2.0:1 points) on the
dipole element. You're stacking distance is pretty miniscule so I think you've
got some major interaction. I think the factory recommends 10 feet. With the
402CD you can get as close as 6 feet but 2.5 feet is really too close. Try
turning the element 90 degrees and see if that makes any difference.
What I have noticed in terms of stacking/interaction is that the closer
you put the antennas, the worse the SWR. I don't have any idea what's
happening to the patterns though. If your SWR is acceptable, you've got some
other effects going on. Time to look at a new mast or another way of doing it.
73, Steve K7LXC
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