In the ongoing discussion about Eugene's antenna, he says:
> 4. You will notice that the 160m wire [C+D] at a length of 130â in the
> diagram would still leave me with about 48â of rope from the insulator to
> the tree. Is there any other approach I could take to make more use of
> this wire? One nice gent suggested that I use the entire length for 160m
> (namely 180â) and let the tuner do the rest. Pros? Cons? Hate to not make
> use of 48â ! donât know why, just seems a shame ï
I believe that an inverted-L is usually used as a space-saving option to try
and approach quarter-wave vertical performance without using a quarter-wave
of height, correct?
Grossly paraphrased, the literature has always said (on 160M) "as little as
30 or 35 feet vertical is enough. The horizontal part doesn't radiate but
acts as loading to make the antenna resonant" right?
Really it radiates some, but just not as much as the vertical part, right?
Modeling inverted-Ls shows the pattern to be like a vertical, right?
The current max point is a quarter wave from the end of the wire, which puts
it at the base of the vertical part, right?
If Eugene has 140' of a 180' wire horizontal, on 160 the current max is up
in the air above his house someplace on the horizontal part of the wire,
right?
My feeling is that this antenna would not perform like a vertical in that
case, rather a horizontally polarized antenna 1/16 of a wave above ground.
I'm not near my modeling equipment, so I can't check it - but some of you
readers are old and wise and probably don't need no stinkin' modeling
software to realize that what I say is true - or is it?
Mark, N5OT
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