[TowerTalk] phasing question

[Signal Hill Ranch]

At 10:32 AM 2000-11-17, you wrote:
>Purely a theoretical question.
>I have no plans nor have heard of any to do this.
>
>I know you can phase multiple beams on one tower.
>Can you phase a beam on multiple towers?
>
>I'm purely guessing that you could carefully calculate the proper coax
>between the towers but also guessing that the increased length and it
>subsequent loss would defeat the idea.

For any given direction there will be a particular line length
that will be appropriate.  But if you want to cover 360 degrees
of azimuth you would have to take into account the angle of the
signal relative to the orientation and spacing of the towers.
This means that there is no ONE line that is proper.

If the towers are multiple wavelengths apart then each particular
phasing line will have multiple azimuthal angles for which it
will work.  In actuality it is possible to use only a few different
lines (say 0 deg, 90 deg, 180 deg, and 270 deg) and have pretty
good results for all azimuthal angles.  But it will require
switching in different lines as you rotate the two antennas.

The 80M LARAE used this technique--as described in one of the
early Antenna Compendiums, I believe.

W0UN


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