---- Original Message ----- From: "David 4X1DG" <[email protected]> To: <[email protected]> Sent: Sunday, May 13, 2012 6:30 PM Subject: [amsat-bb] Circular polarization > > > >Is a UHF circular polarization antenna needed for the current operational > >satellites? > >I am planning some work on my antenna system and wonder if the CP > >is needed, or actually, deteriorate the signal by 3dB if the satellites > >are > > using linear antennae?? > >
> The best option would probably be a rotatable antenna, a sat will never be > fully horizontal vertical or circular, sometimes it even makes a > difference when you flip 180 degrees. > > -- >73 Andre PE1RDW Hi Andre, PE1RDW I agree. A rotatable boom by 90 degrees is a very good option for a linear antenna because in a certain moment a sat can send to you a polarization between linear or through circular i.e. an elliptical polarization that can be matched by turning the antenna over the boom. BTW since the polarization changes very rapidly the speed of rotation of the boom must be very fast, let say maximum 10 seconds or less to rotate from 0° to 90° 73" de i8CVS Domenico _______________________________________________ Sent via [email protected]. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb
