[amsat-bb] Re: Polarity questions
mat_62 at netcommander.com
Fri Sep 19 18:53:29 PDT 2008
I may have misunderstood but the way I got it when I was researching
homebrewing yagi's for my sat station is that if you had to fix the antenna
to either RHCP or LHCP and could not switch between the two because of cost
or complexity or whatever other reason that your best compromise would be to
go with linear polarization.
Feed harnesses for homebrew CP antennas are a stumbling block for me as I
don't have a grid dip meter or SWR anylyzer to properly figure coax velocity
and electrical length. If you don't get the phasing harnesses the right
length then you won't get CP anyway.
I use two of the "cheap yagi" designs by Kent Britain in vertical
polarization and rotate them with a homebrew "SAEBRTrack" Az/El rotor box
and old Gemini OR-360 TV rotators. Works well enough for LEO's anyway.
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