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Re: Polarization question to go along with previous email



Hi Jacob,

Before building a circularly polarised quagi, why not try using a
vertically polarised antenna on 70cm for the downlink?

The 9600bps UoSAT-type birds are always earth-pointing (+/- 2 degrees), and
use vertical polarisation.  You should get very good results when the
satellite is to your north, although you may observe some fades as it is
low on the horizon to your south (as Faraday Rotation will be significant
at that point).

Have a go!

73 Chris vk6kch

p.s  This doesn't apply to most of the other types of satellites.

At 12:10 AM 24/10/1999 EDT, you wrote:
>From my last email I was talking about building circular polarized quagi's.
>
>In the process of designing this project I learned about 2 quagi's on the 
>same boom ofset 90degrees/ 1/4wanelength. After some more reading not to
sure 
>how to set it up as to the polarization WITHOUT a switching system.
>
>EXAMPLE: Above antenna is built without a way to switch which antenna has
the 
>phasing delay harness in line. So if the forward (verticle) antenna is at 
>0degrees and the later (horizontal) antenna is at 90degrees delay would that 
>give me right-handed or left-handed circular polarization?
>
>OR am I totally mistaken and don't need the phasing delay line segment at 
>all??? Since the antennas are already 90degrees out of phase since they are 
>ofset 90degrees/ 1/4wave seperation on the boom already?
>
>PS: Still no credit card. Tried to get it from the WIFE and now I am missing 
>a few fingers...  :-)
>
>73's Jacob Tennant,KB8QIR
>----
>Via the amsat-bb mailing list at AMSAT.ORG courtesy of AMSAT-NA.
>To unsubscribe, send "unsubscribe amsat-bb" to Majordomo@amsat.org
>

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