If you can map your entire noise horizon, and point to a single major
noise source where Xing that out is the issue, then what you are after
is a NULL not a gain node. Two elements, with the NULL precisely tuned
and aimed, will do it for you.
If your noise is uniform all around, then you want front-to-back,
front-to-side, WITHOUT major lobes in the rear or side. Plus whatever
gain you can muster forward.
In my area I need to kill a hemisphere centered on 195 degrees. Sharp
gain to NE is irrelevant unless it comes with the killed back
hemisphere.
Design the pattern to deal with your personal noise horizon.
73, Guy
On Thu, Sep 27, 2012 at 4:26 PM, Jim Sorenson <kjsorenson@gmail.com> wrote:
> Gentlemen,
>
> I have a clear triangular area on my lot that would contain a 3 element
> array such as the K7TIR (http://www.k7tjr.com/3element_2.htm).
>
> I'm presently using a rotatable flag hung from the limb of an oak tree and
> the bottom is about 30 feet up. I'm 23 miles from Pittsburgh and keeping
> the null on Pittsburgh noise is the position I use most of the time. I
> might as well point it NE and leave it that way. In general I do not have a
> serious noise problem though. However, I'm wondering if the a 3 element
> array would be worth the trouble for me? I am surrounded by tall oaks for
> one thing. The xmit antenna is a wire T hung from a line between two oaks
> and tops 80 feet.I run about 80 to 90 radials after the grass stops growing
> here. It gets out very well. I've included an image with all the
> information below in the hopes that I might receive some comments and
> advice concerning the best way to go.
>
> W3BH Lot
>
> https://picasaweb.google.com/lh/photo/_-Akztq6Ro7o0PSzpG8sxtMTjNZETYmyPJy0liipFm0?feat=directlink
>
> The area inside the triangle that is on the lawn is 239 - 196 - 202
> approximately. I could run some short beverages during the winter but would
> be maximum 350 feet and not in all directions. I could probably do 4
> elements, but one of them would be right in the woods.
>
> Many thanks in advance for your comments and advice.
>
> Jim
> W3BH
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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