Guys, I am probably completely off the wall here. But given all the talk about
a 300 foot vertical not working well on 160 and a very high dipole not working
well on 160 leads me to a very unscientific "conclusion" or a possible real
hypothesis...... That super low angle radiation is NOT a good thing for 160.
Given the other anomalous behaviors of 160, like the early morning enhancements
and that antennas with a major high angle component and a relatively minor low
angle radiation component seem to do quite well on 160...... 80 meters, too,
for that matter.
That certainly isn't all of the low band anomalies, but these are a couple we
all have certainly experienced. Given these and others, I am tending to think
that the quest for really low angles of radiation is counterproductive......
and not so surprisingly, counter-intuitive, as well. There is, obviously, a
"sweet spot" for lower angle radiation on 160. Additionally, I am beginning to
think that it is as unique as the band itself. For example, higher bands seem
to favor the lowest possible radiation angle that can be produced...... Could
it be that 160 "prefers" something closer to, let's say 45 degrees? Not
meaning that 45 actually IS that magic number, but maybe close to it????
Closer, anyway, than a 5 degree angle?
Just a thought..... No basis in hard data, but these general anomalies (now
THERE is an oxymoron if there ever was on) seem to be piling up..... to these
untrained eyes, anyway.
Mike AB7ZU
Kuhi no ka lima, hele no ka maka
On Oct 24, 2012, at 12:09, "Tom W8JI" <w8ji@w8ji.com> wrote:
>> Just to point out that we don't have measurements of arrival angles at the
>> ionosphere proving the fields shown in a NEC far-field analysis, either. Yet
>> people seem to accept a NEC far-field pattern as gospel, even though it does
>> not accurately show the radiation launched by a monopole at elevation angles
>> below 10 degrees or so.
>
> We have a lot of things we claim as fact, even though we don't supporting
> data. Some border on magic.
>
> That's why I A-B test things for several months before deciding anything.
>
> :-)
>
> I installed a 300 foot tower because I remembered how well a dipole at 300
> feet worked at a BC station. I was sure, based on the DX contacts, the dipole
> was a killer antenna for receiving and transmitting. Problem is when I
> finally installed that wonderful antenna after all that work, my vertical
> tied broadside to the dipole and badly beat the dipole off the dipole ends.
>
> 73 Tom
> _______________________________________________
> Topband reflector - topband@contesting.com
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