Dang Tom..... I just sent out a more wordy version of what you just said. This
is getting strange. Not sure why it hasn't been disseminated yet (my email),
but I swear I sent it just moments before your email hit my system.
You just added some fuel to my fire. Short version: I, with my rather
inexperienced eye (160 experience, that is) is seeing a pattern that seems to
indicate what we would call low radiation angles aren't really optimum for long
range 160 communications. The other email goes into a little more detail in
why I am thinking this way. Morning enhancement, especially with high angle
radiators (like mine) where I am working Japan and Chile on a radiator that can
very truthfully be called an NVIS antenna. On higher frequencies, a scaled
version of my antenna wouldn't radiate a signal out of the southwest region,
much less thousands of miles distant.
Just a thought! Again, my other email expounds a little more, but this was the
conclusion in a nutshell. Maybe "low horizontal" antennas really ARE better on
160 than they should be..... Given our experience with low antennas on the
higher bands, it seems counter-intuitive..... But there it is.
Mike AB7ZU
Kuhi no ka lima, hele no ka maka
On Oct 24, 2012, at 17:12, "Tom W8JI" <w8ji@w8ji.com> wrote:
>> If we knew those, then we could calculate the location and distance of the
>> signal hops. That might give us some insight as to why some people have
>> found a taller monopole to be worse than a shorter one at a given distance.
>
> Back in the 70's or 80's there was speculation a low angle was lossy from
> grazing along, based on others having poor experiences with taller verticals.
> The top of my tall tower had some antennas and side arms which top loaded it
> a bit, but not much. Certainly the wave refracts gradually at a minimum, and
> so I think distance would not tell anyone much. There have been a host of
> theories since the 1960's, even some from Stew the real W1BB. :-)
>
> I don't know what happens when it gets up in the soup, although people like
> K9LA should be pretty well versed on it. I only know things behave
> differently all the time, and what antenna generally works most of the time.
>
> For example, at sunrise most of the time almost anything reasonably efficient
> works about the same here. It's more a matter of ERP at any not-too-low angle
> and any polarization.
>
> 73 Tom
> _______________________________________________
> Topband reflector - topband@contesting.com
_______________________________________________
Topband reflector - topband@contesting.com
|