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Old December 18th 08, 09:09 PM posted to rec.radio.amateur.antenna
christofire christofire is offline
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First recorded activity by RadioBanter: Oct 2008
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Default Would a discone cover all the US TV broadcast Freqs?


"Jim Lux" wrote in message
...
Hal Rosser wrote:
"Cecil Moore" wrote in message
...
JB wrote:
Discone is vertically polarized and TV is horizontal. Results in a
15db or
more loss in signal.
How about a dual-discone mounted horizontally?
--
73, Cecil http://www.w5dxp.com


If I did that, the omi-directionality (if that's a word) would go away
and so would most of the compactness needed foe stealthiness.
So - does anyone know of an omni directional horizontally polarized wide
band antenna?


Somewhat tricky..

Two crossed dipoles fed with the correct phasing is very close to that.

Check out "Lindenblad" or "turnstile"



A Lindenblad array (e.g. http://www.bbc.co.uk/rd/pubs/reports/1991-15.pdf
Page 9) can provide good circular polarisation over much of a sphere and is
a relatively complicated antenna to design if it is to match properly -
probably over the top for the stated application. But the turnstile, and
the Alford loop
(http://books.google.co.uk/books?id=1...sult#PPA123,M1
as used at DVOR stations), are simpler and can provide good omni patterns in
the horizontal plane and thereabouts for horizontal polarisation.

Chris