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Old August 10th 09, 02:23 PM posted to rec.radio.amateur.antenna
Art Unwin Art Unwin is offline
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First recorded activity by RadioBanter: Mar 2008
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Default Circular versus linear polarization

On Aug 10, 6:29*am, Bob Bob wrote:
Jeff/Art

Keep in mind too that cross polarized (circular) point to point links
(ie with a CP ant at each end) suffer from odd reflection attenuation
(ie the polarization sense gets reversed by reflection)

In 70cm UHF experiments I did back in the 80's I found out that a
horiz-horiz system (base to mobile) outperformed a circular-circular by
at least 12dB when moving. This wasnt actually the base reason for the
experiments so I didnt make accurate measurements.

OT Art, but I hope interesting.

How random is the propogated linear antenna HF wave polarization and
does it vary much with single hop and/or high angle? That might be a
starting point for determining how useful CP on HF might be.

Tnxs for the link Jeff.

Cheers Bob VK2YQA

Jeff Liebermann wrote:
On Sun, 9 Aug 2009 21:24:01 -0700 (PDT), Art Unwin
wrote:


The majority of antennas used today are (commercial) circularly
polarized


What stands out for me is the audio improvement.