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Re: A couple newbie questions for FM birds...


The problem with vertical antennas (or any fixed polarization) is that the 
polarization of the signal to and from the satellite rotates, due mostly to 
Faraday rotation.  For reliable access, you will need either circular polarization 
(preferably switchable) or else the ability to rotate the antenna in the 
Z-axis yourself, either by hand as in the case of the Arrow, or with motors.

That's one reason why car-mounted whips don't do very well.  People have used 
them  to make contacts (including me) when the polarization is favorable, but 
on the whole the results are disappointing.

If a full az-el satellite array is not practical in your situation, one 
possible compromise you might look into is the "eggbeater" antenna.  You'll need 
two of them, one for 145 and the other for 435.  They are made commercially by 
M2 (www.m2inc.com) or you can build your own (see http://members.aol.com/k5oe/).

Good luck & 73,

Ray, W2RS
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