If you could phase these so as to generate and receive cochlear polarization
(90 deg), either LH or RH, you might see a very big increase (I think as much
as 6 dB) in rx signal strength from what I've read. That would be pretty cool.
Kim N5OP
"People that make music together cannot be enemies, at least as long as the
music lasts." -- Paul Hindemith
> On Nov 23, 2014, at 15:04, "Rick - DJ0IP / NJ0IP" <Rick@DJ0IP.de> wrote:
>
> (changed the title from 17m..)
>
> Again an excellent paper from Jim.
> Had one quick read.
> This is going to take days to digest and consider.
>
> Although it is obvious to me that height is important, this is the first
> time I have seen it quantified.
> Vy gud.
>
> My favorite line in the entire paper was:
>
> "Don't let "great" become the enemy of "good"... (or something like that).
>
> EXACTLY MY POINT on nearly all of the antennas I post on my web site.
> Most of us will never have a great antenna, for a long list of reasons:
> e.g., Space, Money, HOA, XYL, Neighbors, etc.
>
> There are a lot of simple antennas that work and work well.
> And there is no single one which will work best for most people.
>
> Each of us must evaluate our own situation, under consideration of the
> points above and determine what is going to work best for us.
>
> BTW Jim, if you ever want to do an increment to the paper, I would be
> interested in seeing how much difference rotating the dipole will make in
> real life at various heights.
>
> On the other hand, if you can manage to have two dipoles perpendicular to
> each other, there is no need to rotate.
> I have only ever had that once in my life and it was on 80m with both
> dipoles 75 ft. high.
> The results varied from no difference at all, to several S-Units.
>
> We have a d-i-y add-on to our 3-band or 5-band wire Yagi antennas which
> adds a short end-loaded 40m dipole to it, but rotated 90 degrees. It uses
> the 20m director and reflector for capacity end-loading.
>
> We have enough installations of this antenna in the field to conclude that
> when compared to a fixed full-size wire dipole at a similar height, there is
> no noticeable difference in most directions but in some directions
> (presumably off the ends of the fixed dipole), the short dipole is several
> S-Units stronger. We have never measured this with instruments, but
> experience it every time we use the antenna.
>
> It would be nice to see this quantified, so Jim if retirement life is boring
> you a little, here's a little distraction for you! (hi)
>
> Thanks for the paper and the link, Jim.
>
> 73 - Rick, DJ0IP
> (Nr. Frankfurt am Main)
>
>
> -----Original Message-----
> From: TenTec [mailto:tentec-bounces@contesting.com] On Behalf Of Jim Brown
>
> This link is to a slide show for a presentation I've done several times
> about this set of issues. It doesn't address delta loops, but it does
> compare horizontally and vertically polarized antennas at various mounting
> heights.
>
> http://k9yc.com/VertOrHorizontal-Slides.pdf
>
> 73, Jim K9YC
>
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