The original post was about using a C31XR on EIGHTEEN POINT ONE MHz.
That's a band it was not designed for. And that a low dipole would
beat it.
Where did you get **TEN** meters from? Stick to the subject.
Propagation on 18 is a lot most like TWENTY meters, anyway.
And will anyone mention that this angle business is a very sparsely
supported "science" with a lot of unanswered questions and modes, and
lots of unexplained contrary anecdotal material.
Used a 15 foot high fifteen meter dipole as a teenage Novice operator
in Kentucky. Since nobody had tried to tell me that all that energy
would go straight into outer space, I went ahead and worked a couple
thousand contacts on it, more USA than not. I got lots of 599/589
reports running a mere 50 watts, at a time where you had to get the
QSL address over the air because you couldn't afford a call book, and
the automatic 599 hadn't been invented yet.
I worked all the surrounding states on 15 meters. This on a frequency
higher than in the original post. How does one do that if those angle
formulas are really absolute and trustworthy?
***!!!>>> Or is it really that the angle formulas describe a rather
broad and fuzzy center of probability, with a lot contrary evidence
suggesting that there is something yet to be discovered?
18 MHz dipole at 20 feet will work. Easy experiment. Try it. See how
many Europeans you work and get 5NN as a report.
73, Guy.
----- Original Message -----
From: <n4kg@juno.com>
To: <TOWERTALK@contesting.com>; <swca@swbell.net>
Sent: Monday, June 24, 2002 8:39 AM
Subject: Re: [Towertalk] Re: [Force 12 Talk] XR dilemma
> Hi Mark,
>
> I think our main disagreement comes over the the maximum
> angle that is supported on 10M. I believe that to be around
> 20 degrees (at very high MUF's).
>
> Some time ago, someone plotted his 10M SS contacts on
> a map. The vast majority were at skip distances of 900 miles
> or more, which corresponds to a 20 degree takeoff angle.
>
> At 18 ft, a 3L 10M Yagi places the majority of it's radiation
between
> 20 and 30 degrees. 3 dB points are 15 and 40 degrees. Over
> 80% of the energy is above 20 degrees, i.e. going into outer space.
>
> At 35 ft, the 3 dB points are 7 and 22 degrees with the vast
> majority of the energy falling in the range of angles supported
> by the ionosphere. I see NO BENEFIT in going lower than
> 35 ft on 10M.
>
> Tom N4KG
>
>
>
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