Billy wrote:
>
> Lots of good advice ... one point that I've not seen mentioned,
> is to make sure adding those elevated radials DOES NOT
> mess up the pattern of the lower yagis. As in adding those
> 130' wires, in the area of the 27'/etc. yagis rather defeats the
> reason you went with the Phillystran ...
>
> My vote is to feed it at the base, lay out the radials, and don't
> worry, make QSOs. That way you won't risk messing up the
> stacks on 10m and 20m.
>
> 73 Billy AA4NU
I agree. I just put up a Yagi on a short tower. I made the whole mess into
an L on 160 and screwed up the pattern on my new antenna. What happened?
Basically lost the front to back I enjoyed before the shunt was dropped in
place. I modeled it and was shocked to see the resultant pattern with and
without the shunt in place. When I rotate the beam in the model, the
pattern skews are quite apparent. Admittedly, the top member of the shunt
is only 5' or so from the yagi. Perhaps you would have better results. In
my model, when that horizontal member is parallel to elements, the pattern
goes to heck and I see lots of current on the drop wire. I haven't decided
how to fix it yet--rain and sleet prevent even thinking about it.
Ford-N0FP
ford@cmgate.com
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