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Re: Antenna Questions

>From: "Tim Cunningham" <tim_cunningham@mindspring.com>
>Are there any studies or data that show the effects (attenuation)
>when one of 2 circular polarized antennas with compatible sense
>are off-pointed at various angles ?

I'm not sure of studies, but what you are asking about is well known to
experienced AO-10 and AO-13 operators.

>This would produce what I believe to be an elliptical pattern, but
>is  there any data to support the perceived attenuation at the
>receiving station provided it is pointed at the off-pointed CP

You are correct, and not only that. For increasing squint angles
polarization sense will become linear and then reverse as seen by the
observer.  The answer is to use a CP antenna with polarization switching.
That way you never experience more than -3 dB fades due to this effect.
Squint angle polarization effects are addressed in chapter 7 of the
Satellite Experimenters Handbook.

Hope that answers your question.

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