I am right now using an inverted L which is spaced about 4 feet away from my
tower. The vertical leg is about 85 feet. I only have 6 radials at the
present time
Now here is the question
The horizontal leg is about 50 feet and goes to my back yard. Since the
trees are not that high, it probably slopes down to 40 feet at the far end
The horizontal wire faces west..
Would it help me to face that wire to the south for east west signals on
transmit. I am hearing very well with a 550 foot beverage. >>>
At any distance less than 1/4 wave or so, which is around 130 feet, the
inverted L is coupled very tightly to the tower. At wider spacings, like
50-100 feet, the tower and things on the tower **sometimes** won't have much
interaction. Of course if you are unlucky, interaction can be severe even at
a hundred feet spacing or more.
You have a particularly close situation. For all purposes, at less than a
few dozen feet spacing, the tower and inverted L are really just one big
antenna system. The tower characteristics, including ground system and
cables leaving the tower, and all the guy wires and things on the tower, are
all part of that inverted L system. The tower can suck up a lot of RF and
divert it to places that hurt your signal, even if the tower system is not
resonant. This would include lossy ground below the tower, and all the
cables and wires leaving the tower.
Much more critical than the direction you run the flattop, which is probably
only worth part of single dB, is how the tower is constructed and wired. If
the tower has no radials, or has uninsulated guy wires going to anchors, a
considerable amount of energy can be dissipated in lossy earth. How much of
a problem it is really depends on details of the tower installation more
than anything else.
73 Tom
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Stew Perry Topband Distance Challenge coming on December 29th.
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