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Re: Has anybody heard AO-10 lately ?



My guess is that you have never worked AO-10 before.  If you did you would
know that your statements are incorrect.

My statement was that the circular polarization VARIES.  This means that at
one minute, you can be LHCP, and the next your signal drops to nothing.
Switch to RHCP and you get full strength.  This happens on uplink AND
downlink and they can literally be different.  So using a linear antenna IS
still a disadvantage.  The signals will never be linear.  They may be
elliptical or circular, but not linear.  CP antenna is still the best.

I stand by my statement.

73,

Jon
NA9D

> >One more thing:
> >
> >AO-10 has a circular polarization that varies.  The Arrow is a linearly
> >polarized antenna.  You loose 3 dB of signal there as well.
> >
>
>
> Since there is no attitude control for AO-10, there is no guarantee that
> the circular polarized antennas are pointing toward you on earth.  With
> that in mind the 3dB loss does not apply.  While it may be true that a
> circular polarized antenna will provide a better average overall signal
> than a linear polarized antenna, it is very easy to roll the Arrow antenna
> to change polarity as the incoming signal changes throughout the orbit.
> The point is the signal from AO-10 may be circular polarized, but if the
> antenna is not pointed toward you the resultant received signal will not
> be truly circular polarized when your antenna detects the signal on the
> receiving end.
>
> When working AO-27, UO-14, or SO-35 I find that rolling the Arrow
> antenna to change the polarization during an orbital pass change make
> a big difference.  Relativity plays a part as the satellite tumbles and
> moves through its orbit. I have not used it for AO-10, but now I am
curious.
>
>
>
> Tim -  N8DEU
>
>
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