On Feb 24, 5:16*am, Art Unwin wrote:
On Feb 23, 10:35*pm, tom wrote:



Jeff Liebermann wrote:
On Sun, 21 Feb 2010 21:44:56 -0800 (PST), Art Unwin
wrote:

On Feb 21, 11:18 pm, Jeff Liebermann wrote:
On Sun, 21 Feb 2010 19:45:03 -0800 (PST), Art Unwin

wrote:
Model of 2 element multi polarization.
http://users.sdsc.edu/~unwin/art/Picture6.png
http://users.sdsc.edu/~unwin/art/Picture7.png
http://users.sdsc.edu/~unwin/art/Picture10.png
http://users.sdsc.edu/~unwin/art/Picture11.png
I don't see a model. *There is no .EZ, .GAA, .N4W or .NEC file for me
to play with and tear apart. *I can't even tell what the antenna looks
like from what you've posted. *

You have two elements each located with x,y and z *co ordinates at
each end, so you make your own file to suit the program you intend to
use or is available.

I do not have two elements. *I can't located them in x, y, or z
because you didn't specify any such coordinates. *I can make a
suitable NEC deck, but *YOU* need to supply the numbers.

Jeff

I hate to support Art, but he did give the endpoint data in picture6. *I
modeled it with eznec+ 5 and the pattern and gain are reasonably close
to what he shows in the other "pictures". *Close considering he appears
to be using mininec and if he includes conductor loss and real ground
it's off a fair amount (I show 9.36 dBi gain). *I didn't run circular,
and doubt that it has much in the way of circularity, which is kind of
obvious from the elements. *Even though they are skewed in a way which
he probably patented.

tom
K0TAR

I got the same gain as you using lower segments but it went up when I
doubled the segments so I held to that figure. I thought I provided
the cp and it was something like 3 dbi down which is much better than
20 dbi or more down if the array was not sensitive to cp. The same
segment problem occured again when modeling the
*Beverage in circular form as it requires a tremendous amount of
segments to get total accuracy but the actual antenna in practice
showed conformality to make me comfortable. The same problem occurs
again using wire mesh and it would cost me near $1000 to acomplish
that but in practice it functioned very close to the circular wound
Beverage. The best antenna in the trials appeared to be *long dual
wire mesh curtains which I checked out on top band tho conditions were
not consistent to hang my hat on. I intent to check out the "tilt"
action during the coming year using "garbage can" shaped mesh and at
ground level.
The whole point of the modeling was to show two FW elements that were
not planar or parallel provided an array that was sensitive to more
than a yagi built for horizontal gain alone. This to my mind makes it
a more efficient antenna for conversion of signals that hit it.
Another interesting point showed up with the circular beverage which
clearly merges the two vector radiations instead of the saucer shape
radiation from the earths rotation vector
and the gravity vertical column radiation that is added to the above
to form a planar yagi radiation form.

if you wind a wire into a coil it is NOT a Beverage antenna. And note
it is properly Beverage with a capital B since it is named after it's
inventor. go invent something useful and make up your own name,
don't try to distort a perfectly good antenna that has well know
characteristics.