Don't jump on me Jim, I have a pile of information I've accumulated and read
about Beverages (but didn't have KITTT's Canadian government study, thanks
Dave).
Up to now (not having read the Canadian document fully yet), I
couldn't/didn't find a published scientific study where variables such as
height and length for low HF Beverages were conducted under a set of
standard conditions (maybe it is in the report Dave passed along - which
will take some reading).
You are also quite correct that I have not looked in every technical
journal, there are so many not on line or that I don't have access to. I
also don't have the ON4UN book (sounds like a good purchase to make) and my
ARRL Antenna Manual is dated and its coverage of Beverages still didn't
answer my questions.
I'm impressed you have 'done that study, or done that modeling, or built
those antennas . . . ' I also have built a heck of a lot of antennas in the
60 years I've been hamming. BUT, I have never built or used a Beverage nor
had a 'real' 160M setup which I'd like to rectify in the dwindling years
left.
I've learned a lot from the discussions here on the subject, one being that
there is often a difference of opinion on many of the issues that have been
posted, which is quite helpful, allowing one to see more sides to an issue.
I thank all of those who have put forth their experiences and thoughts and
beliefs.
And Jim, while I didn't ask about the use of Beverage's on bands other than
160 M, thanks for the comments. And I understand VE7RF's comments.
I am concerned that, since I have never used a Beverage, built a Beverage,
and only recently began pulling together articles and reports about them
before reading the recent posts on Towertalk, that you feel I shouldn't ask
questions unless I am fully versed in the topic. The reason for the
questions is I am NOT fully versed. I don't know a better way to learn than
ask questions. but apparently you feel otherwise.
I apologize to you for apparently wasting your time and shall just become a
passive reader.
Don W7WLL
-----Original Message-----
From: Jim Brown
Sent: Monday, February 02, 2015 11:14 AM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] Beverage Antenna
On Mon,2/2/2015 10:05 AM, Don wrote:
First, I'm surprised there does not seem to be any published measurements
taken at a common test site of a Beverage at various heights and lengths
(such as done with yagi's, and other antennas on test ranges).
Why do you assume that nothing like this exists? Beverages have been
around for nearly a century, and it is quite likely that there's a lot
of published work that you haven't looked for in scientific journals.
It's also possible to model antennas like this and do your own study.
There's a lot about Beverages (and other RX antennas) in the ON4UN book,
and in the ARRL Antenna Book.
Email reflectors like this one should not be a substitute for pulling
out the books and studying them. Many of us who post answers to
questions like this have done that study, or done that modeling, or
built those antennas, and are sharing what we've learned. As VE7RF has
noted, optimum height is a function of wavelength. When a Beverage is
higher than that, it doesn't stop working, like throwing a switch, it
just becomes less effective. My 550 ft Beverages, a full wavelength on
160M, at an average height of 5-6 ft, are quite effective on 40M, and
are still working on 20M! How do I know? I run diversity with my K3
using the TX dipole at 125 ft into the main RX and the Beverage into the
second RX.
73, Jim K9YC
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