On 10/18/20 12:24 PM, kq2m@kq2m.com wrote:
Hi Alan,
I saw that too but it doesn’t answer my questions. "Radiation across the
diagonals" is a vague and unhelpful statement. It doesn’t address in
what directions the elements should placed nor which elements are
effectively being phased and radiating to produce the NE direction
radiation.
73
if your 4 square is arranged so that the sides of the square are N/S and
E/W (so you have elements at NW, NE, SE, SW, going around clockwise),
then the "beams" are going to be along the diagonals of the square (so
you can form a beam pointing NE, SE, SW, NW, etc.)
In the NE direction, the NE is lagging 90 degrees, the SE and NW
elements are phased the same, and the SW element is leading 90 degrees.
This makes the current distribution (in the beam direction) 1:2:1..
The actual hybrid generates 0 and 90, and you reverse the phase to get -90.
(there are reasons why you might want to use something other than 90
degrees, or alternately, space the antennas differently than 1/4
wavelength apart - but let's leave that for now.
You can also form an alternate phasing - Feed NE and SE the same, and NW
and SW with 90 degrees leading to form a beam pointing East. (this is
basically like two arrays in parallel)
http://tm1o.free.fr/4SQ/80m/en_ver_final4-sq_03_04_15.pdf is a handy
reference
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