I have built a homebrew version of the RX 4 Square and it does not seem
to work very well. I have double checked everything. I must be
overlooking something.
I used the FET follower circuit from K7TJR with 14 foot long whips made
from fiberglass fishing poles from Wall Mart. I made the whips by
winding 14 foot of #20 AWG insulated wire around 13 foot long
Shakespeare "pan fishing" pole that Wall Mart sells. I mounted the poles
to the top of 4 foot long steel posts taking care to not cause high
shunt capacitance. Each antenna has a 3 foot ground rod and 4 x 16 foot
long short radials. I built the preamps into plastic boxes taking care
to make them all as identical as possible. I built the phasing/switcher
from the latest Low Band Dxing. My phasing and feed lines are Alpha
9803C RG-59 foam coax with a VF of 78% and all cut from the same roll.
My long phasing line is 44 feet and the two short lines are 22 feet. My
antenna diagonal spacing is 62 feet 8 inches and my side spacing is 44
feet 4 inches. I used 1/4 wave on 80M feed lines to each antenna which
are 48 feet 8 inches long.
One problem I have is a small yard and the SW vertical is about 5 feet
from a large metal building and the NW vertical is 2 feet away from a 3
foot high metal wire fence.
The NE vertical is 3 feet away from my SE/NW 300 foot long reversible
beverage antenna. And my NE/SW 300 foot long reversible beverage runs
down through the West side of the 4 Square antenna spaced midway between
the verticals.
The 4 square shows - very poor - to no - directivity and when it shows
directivity it seems to be to the wrong heading. When I use the 4 Square
the beverages are terminated on both ends. And my TX vertical is
detuned.
On 160M, 80M and 40M the short beverages work much better than the 4
square. Would the short beverages be that much better than the small RX
4 square?
Is there any type of Rxing antenna that could use the side of a large
metal building as a reflector on 160M, 80M and 40M. The building aside
of my yard covers the boro reservoir. It has no wiring or noise making
electrical equipment inside, just a cement reservoir filled with water.
The building is 60 foot by 80 foot and 15 feet tall. And I can use the
sides as reflectors. Could this be used some how with a Flag or Pennant
antenna to improve its performance?
TNX es 73,
Mike W3TS
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