I don't know how useful this will be for you. But here is how
I'm configuring a single tower HF antenna system for 40 through
10 meters.
I live on a 192 foot AARZT hilltop with broad, relatively flat
river (wash) valleys extending out 5 to 8 miles in the important
directions. I'm putting up a 70 foot tower. At the top will be
a full sized three element 40 interlaced with a full sized three
element 30 on 40 foot boom (2 feedlines). At the 40 foot level
on a tic ring rotator will be a 12 element LPDA coverng 14 to 30
MHz (30 foot boom, one feedline).
The 30 / 40 interactions have been accounted for in the design of
the antenna so there won't be a problem there. The only
significant interaction I'm expecting between the two separate
antennas is on 15 meters. Since I can rotate them independently,
I can eliminate that one when necessary.
So there you have it. One tower, two antennas, three feedlines
covering all ham bands from 7 to 30 MHz with rotatable 20ish dB
F/B patterns on all bands.
73, Eric N7CL
>From: KI7WX@aol.com
To: <towertalk@contesting.com>
>Date: Tue, 19 Oct 1999 21:36:41 EDT
>
>Well I must admit it was a longshot to find someone that had
>tried the Skyhawk and the XM240. Thanks to those that reponded,
>nothing new but I do appreciate the time it takes to type in an
>answer.
>
>Let me try another angle at the same issue and see what folks
>are doing/thinking. I hope it's not a waste of bandwidth, but
>effective one tower stations are interesting to the majority of
>TT participants I think.
>
>Assuming a 100-110 foot tower with goal to cover 10-40M
>effectively. The approach that makes sense to me is a three
>stack of tribanders spaced about 30-35 feet and a 40M 2L yagi up
>top. This has worked for a lot of guys already so very little
>reinventing of the wheel to be done. The assumption, however,
>is that the 40M 2L can coexist well with the tribander and have
>sufficient bandwidth to cover 40M. The latter pretty much rules
>out the linear loaded 2L 40 shorties and leaves the Cushcraft.
>I don't THe 402CD seemed to do this nicely while the XM240 may
>not.
--
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