[amsat-bb] Re: Polarity questions

Michael Tondee 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.
Michael, W4HIJ 

More information about the AMSAT-BB mailing list