Hi Guys,
I have several interrelated questions and would appreciate your thoughts....
Currently I have two towers located 110' apart. Tower 1, with 5 40 & 20
yagis on it, is 130' tall and around the tower is an 80 meter Inv L 4-square
with the elements supported on 4 separate trees. The tower is in the middle
of the 4-square.
Tower 2 is 100' and has 8 10 & 15 meter yagis on it. With a 40 meter
4-square located 90' feet away.
ALL 4-squares currently have 4 raised radials per leg and are about 10' off
the ground at the feed point.
ALL the guys wires on both towers are broken up with LOTS of insulators with
no more than 27' of guy wire at any point between insulators.
I am currently considering moving the 80M 4-square to the small tower and
hanging the elements from it via ropes to set up an Inv L 4-square. Then I
will hang the 160 elements for a 160M Inv L 4-square from the big tower via
ropes.
At one spot between the two towers, one of the 160M elements and one of the
80M elements will be within about 10' of each other. These would be the
160m NE element and the 80M SW element.
On the other side of the tower, the 80M NE element will be within 30' of the
40M SW element.
My questions:
All the 4 squares will continue to have 4 raised radials per leg at about
the 10' level. 160M 4 square will have legs at about 15' above ground.
1) Any serious problems with having the 160 & 80 4 squares so close
together?
2) Currently the 80M 4 square elements are no closer than 40' from the
tower, however, when I hang the ropes of the tower from the 85' level, the
top of the 80 M elements will be within about 5' of the tower. Will this
hurt the 80M 4-square performance any further? The elements hang vertically
for most of the distance but then the top 15' of the element will slope
toward the tower at about a 45 degree angle.
3) The 160 M 4-square will also have elements hung by rope from the 115'
level and the most of the element will be vertical but the top part of the
element will slope toward the tower at about a 45 degree angle and at the
top will be about 5' from the tower. Will this hurt performance
significantly? How might the F/B, F/S and freq. of minimum "dumped power"
be affected?
4) How much might the 40M 4-square performance be hurt by the presence of
the 80M 4-square so close?
5) One of the elements of the 80 M 4-square will come within about 20' of
the house. Is this too close? Will it cause problems with the 4-square
when pointed "at the house"?
6) How far apart must I keep the 4-square legs from any beverage?
7) How far apart must I keep the raised radials from any beverage?
I am NOT going to try to model this. It is much too complicated.
Any thoughts and or practical experience would be appreciated! Many thanks
for your help.
73
Bob KQ2M
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