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Re: Polarization question to go along with previous email



On Sun, 24 Oct 1999 KB8QIR@aol.com wrote:

> In the process of designing this project I learned about 2 quagi's on the 
> same boom ofset 90degrees/ 1/4wanelength. 

A lot of early OSCAR work was based on mounting two crossed beams on a
boom.  But unless you can track the antennas "perfectly" it is a waste of
time.  Lets say you have one beam delayed by 90 degrees to make it Right
hand circular and you are pointed right at the bird.  Great...

But lets say your beams are separated by 4 feet.  And you are off-pointed
by only 12 degrees.  This off pointing now introduces a full 1 foot pahse
delay between the beams.  The result is LEFT hand circular!

Thus, anytime you phase together separate linear antennas (not on the
same axis) you are creating the potential for any and all phase
possibilities (including cancellation) just depending on where you point
them...

(I dont have a calculator handy, so I guessed at the 12 deg)
de WB4APR, Bob


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