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Re: Polarization question to go along with previous email



At 12:10 AM 10/24/99 -0400, KB8QIR@aol.com wrote:
>OR am I totally mistaken and don't need the phasing delay line segment at
>all??? Since the antennas are already 90degrees out of phase since they are
>ofset 90degrees/ 1/4wave seperation on the boom already?

Precisely.

You can place one of antennas 90 degrees (1/4 wavelength in air) ahead of 
the other and drive them in phase, OR you can place the two antennas 
together, and put the 90 degree (1/4 wave in coax) delay in series with one 
antenna.

If you place the antennas with one 90 degrees ahead, and drive them with 
electrically in phase signals, then to switch to the other sense of 
circular polarization (from right to left or vice versa) you would need to 
switch in a 180 degree electrical delay in series with one antenna.  That 
is sometimes a convenient thing to do.  That works because 90+180=270 which 
is like -90.

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