[amsat-bb] Re: Circular polarization

[Andre]

On Sun, 13 May 2012 20:13:40 +0200, Bob- W7LRD <w7lrd at comcast.net> wrote:

>
>
> Agreed... occasionally, sometimes left, right, vertical or horiz will be  
> best.  Then is that for the up or downlink ?  Essentially I have  
> discovered it is a crap shoot.  Whatever works at any given moment may  
> not work (that well)  a few minutes later.   I believe Domenico had a  
> scheme for switching any of the four.  These uncertainty's   make it fun.
>
> still rebuilding all antennas
>
> 73 Bob W7LRD
>
> Seattle
>
>
>
> ----- Original Message -----
>
>
> From: " Ib Christoffersen " <oz1my@ privat . dk >
> To: "David 4X1DG" <4x1dg@ iarc .org>, amsat -bb@ amsat .org
> Sent: Sunday, May 13, 2012 10:44:55 AM
> Subject: [ amsat -bb] Re: Circular polarization
>
> Hi David,
> The short answer is NO.
>
> But there are more to it than that :-)
>
> I think I still have an article about that if you are interested.
>
> 73 OZ1MY/ Ib
>
> ----- Oprindelig meddelelse -----
> Fra : amsat -bb-bounces@ amsat .org [ mailto : amsat -bb-bounces@ amsat  
> .org] På vegne
> af David 4X1DG
> Sendt : 13 May 2012 18:31
> Til: amsat -bb@ amsat .org
> Emne : [ 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