[amsat-bb] Re: AOP-1 Circular Polarization?

[i8cvs]

Hi Ron, W5RKN

The X configuration is the best if you use a metal-boom while the X
or  + configuration can be used indifferently if you use an insulated boom
like fiberglass as demonstrated with experiments by WA5VJB

http://www.g6lvb.com/fibermetalboom.htm

In addition the X configuration is nice if you want to add V and H linear
polarizations using a relay switcher for V-H-RHCP-LHCP as described
into the AMSAT Journal March/April 2007 and May/June 2007

73" de

i8CVS Domenico

----- Original Message -----
From: "Ronald G. Parsons" <w5rkn at amsat.org>
To: <amsat-bb at amsat.org>
Sent: Sunday, May 18, 2008 11:42 PM
Subject: [amsat-bb] Re: AOP-1 Circular Polarization?


> Assuming the antennas you reference do produce circular polarization,
> radiation wise, it doesn't matter whether you mount them in an X or +
> orientation. The only difference would be the phase of the radiation, and
> you are not concerned with that. There could also be a difference between
> right- or left-circular polarization, but whether that matters depends on
> the polarization the the satellite's antenna. But X or + does not change
> that.
>
> There might be some mechanical reason for an X or +, such as weather
> proofing, but not signal wise.
>
> Ron W5RKN
>
> > Date: Sun, 18 May 2008 14:28:34 -0400
> > From: Sebastian <w4as at bellsouth.net>
> > Subject: [amsat-bb]  AOP-1 Circular Polarization?
> > To: Amsat - BBs <amsat-bb at amsat.org>
> > Message-ID: <2D502798-0BC1-4507-98F8-C86CEF5A7590 at bellsouth.net>
> > Content-Type: text/plain; charset=US-ASCII; format=flowed; delsp=yes
> >
> > Hello all, I'm getting ready to put back up my old AOP-1 antennas (the
> > old Cushcraft antennas that were popular in the days of AO-10 & 13).
> > I'm wondering whether I should follow the same procedure of cross
> > polarization for the 440 beam?  It was recommended at the time to
> > place the antenna in an X pattern instead of the cross pattern.  Also,
> > at the time, the 2 meter antenna was suggested to be placed in the
> > standard vertical/horizontal polarization.
> >
> > Please let me know which would be the best method to use for most of
> > today's birds.
> >
> > 73s de W4AS
> >
> >
> > ------------------------------
>
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