Worse than "not the best" or "not a good idea" from prior
experimentation. My two Beverages 6 feet up (10' total Z) over a 4
strand barb wire fence did not work - very poor directivity. One N-S
and one E-W. Then some NEC2 modeling showed 6db directivity over 3
strands of barb wire. However, insulating all fence wires below a 600'
Beverage in 4 places, at ends and at 200' & 400' showed modeling 15db
directivity and 2 more db of gain.
Some good news was the modeling showed 1000' of continuous fence beyond
the ends had no effect. I sold the ranch before insulating the fence. (+
PITA to do it).
Beverage theory agrees with the modeling and experience, so it was a
learning experience for me. Ran the models again with NEC4.2 and got
the same results.
So I learned to not have conductors parallel or nearly so in close
proximity to a Beverage and that the modeling made sense.
Grant KZ1W
On 10/1/2020 15:34, Mike Waters wrote:
Gentlemen,
I am in full agreement with the many statements that Vic Misek's design (at
least in the first edition of his book) is, uh, 'not the best', and a
ground screen (or grounded wire) under a Beverage is 'mostly' *not* a good
idea. Over 40 years ago I was going to built it, but W8JI himself told me
in uncertain terms that it wasn't near as good as a 1λ Beverage (or
something to that effect. ;-)
However, in recent years it occurred to me that a wire or narrow ground
screen under a Beverage *might* not completely ruin its usefulness in all
types of soil, because the Beverage still "sees" the lossy earth on either
side of it to some(?) extent.
This is merely an untested theory of mine, and I have no idea whether there
is any case to be made for it.
*Most of all*, I know of no one who has performed technically-sound,
side-by-side instantaneous A-B F-B, RDF, etc. comparisons. I think this
might be what Jay is thinking about.
I also have heard that Vik has posted revisions to his design in newer
editions. But I am not qualified to say if they are better or not. An
advanced NEC 4.2 model would be better than nothing
Also, Vik's design *might* not be working as a true Beverage, but rather
something along the line of the many different compact receive antennas.
(The K9AY and Shared Apex array are all that come to mind, but I'm not
saying that there are any similarities to either of these.)
Much has been written by Beverage experts in the Topband reflector
searchable archives about this.
http://lists.contesting.com/archives//html/topband/
We would do well to study them.
73, Mike
W0BTU
https://web.archive.org/web/20181115070846/http://www.w0btu.com/Beverage_antennas.html
On Thu, Oct 1, 2020, 3:41 PM Jay <jay@jasonh.com> wrote:
….But my Beverage is 4 feet above the ground. In the new configuration, it
will be 6 feet above ground.
Would a ground screen benefit a Beverage antenna that is 6 feet above
ground?
*From:* bevantennas@groups.io <bevantennas@groups.io> * On Behalf Of *Walter
Salmaniw via groups.io
*Sent:* Thursday, October 1, 2020 4:14 PM
*To:* bevantennas@groups.io
*Subject:* Re: [bevantennas] Ground screen under beverage....
I can add my $0.02 as well. I run BoGs in Masset, with lengths up to
750'. I've tried counterpoises as well. The wire lays on essentially
sand. I have not noticed any value to having multiple counter-poises in my
experimentation. I've tried 2 types: 1 is a single wire upto 100' in
length, and the other experiment was a fan of counterpoises of about 30'
each. Didn't do much of anything, best I could tell....73, Walt
On Thu, Oct 1, 2020 at 8:08 AM <nhp@ieee.org> wrote:
Hello Jay,
It seems to me that there was some disagreement with Misek's idea of using
a counterpoise under a Beverage antenna, based on the principle that the
Beverage antenna works best with a poor ground underneath it. Effectively
improving ground conductivity under the wire seems counterintuitive.
I probably have some notes in old file folders on such experiments that
were done back in the 1970s and 1980s by hobbyists, and I'm sure that I've
tried at least a wire counterpoise myself, but that it didn't seem to be
worth the extra trouble. Otherwise I'm sure that I would have continued
using it in my DXpeditioning days.
The medium wave club, IRCA (ircaonline.org), has a number of reprints,
including some on Beverage antennas, and hobbyist experience with them. The
club is presently in the process of making those available to the general
public, so keep an eye on their website. It should happen in the next
month or so.
best wishes,
Nick
At 04:01 2020-10-01, Jay wrote:
Hello all,
I currently run a 320 foot long beverage using the DX Engineering balun
and resistor. Both ends are grounded with an 8 foot ground rod. I am
getting good results, but I want to improve the antenna. I was reading "The
Beverage Antenna Handbook" by Victor A. Misek, P.E. W1WCR, and he talks
quite a bit about ground. What I want to do is lay a ground screen
underneath my beverage- (1x2 inch by 6 ft wide) welded wire. I will connect
the ground at both ends of the antenna to this ground screen. Additionally,
I am using plastic fence posts from Tractor supply to hold up the antenna
currently. (4ft high) the bottom 6 inches is metal. What I want to do, is
pound an 8 ft ground rod in, and connect that to the ground screen every 10
feet or so, and then leave 2 feet or so of the ground rod exposed. That
way, I can use a hose clamp, and attach the fence post to it, for a more
permenant installation.
Have any of you tried using a ground screen underneath your beverage to
improve the directivity, and lower the noise floor of your antenna?
I would love to hear comments on this idea.
'73,
Jay
Nick Hall-Patch
Victoria, BC
Canada
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