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Re: Has anybody heard AO-10 lately ?




>
>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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