John,
See my post to Jim which describes the land on my qth. I assure you
that the "ground" is not better
than I think, but the hilltop undoubtedly helps in some directions.
The beamwidth is decent for a 4-square with 1/4 wavelength spacing, but
it is even better for
3/16 wavelength spacing between the elements. I did all my plotting
decades ago on
Brian Beezley's excellent program AO program (DOS-based). The biggest
difference between
the 1/4 and 3/16 spacing is at the extreme ends of both sides of the
main lobe,
more than 45 degrees from the center. You really notice the sharp
dropoff between 45- 60 degrees
from the center of the lobe on the 4-square with 1/4 wavelength spacing
and not nearly as
much with the 3/16 wavelength spacing. With the center of the lobe at
45 degrees, that means that I get
better coverage into Africa and UA0, both of which are useful
directions. Likewise, when aiming SW, I get
better coverage into SA and VK. I hear more "stuff" off the sides of
the antenna that I might otherwise
miss. It's worked well for me but others might prefer a narrower
pattern.
Bob, KQ2M
On 2024-07-24 16:44, john@kk9a.com wrote:
What makes you believe that you have a poor ground? A vertical array
with
an elevated counterpoise is still ground dependent so it if works well
for
you perhaps your ground is better than you think!
It has been a while since I looked at a standard 4 square model but I
seem
to recall the beamwidth was pretty large. It would be interesting to
overlay a pattern with closer 3/16 wl spacing and see what difference
there
is 45° from the main direction. Their may not be much difference in
that
direction.
John KK9A
kq2m wrote:
One antenna that does work well even over poor ground is a 4-square
with
elevated radials, preferably above .05 wavelength in height. In my
case
I changed to a different design - instead of orienting the elements in
a
1/4 wavelength "box", I use custom designed 3/16 wavelength spacing to
give a broader pattern which allows me to better hear/work ZS, Southern
Africa and UA0 when pointed at Europe.
73
Bob, KQ2M
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