de 4S7RPG
Have received several comments on my experience with my short beverage. I
know its short - when in Rome do as the Romans do, when in Sri Lanka you
make do and put up with the inadequacies!!
replies were as follows++
From: Jim Henderson <jhenders@zianet.com>
Subject: Re: TopBand: Beverages
Bob OM:
Interesting to note what you heard frpm 4S; I did a lot of 160 from
7Q and 5X a few years ago, and a lot of it was during the worst of the rainy
(ie QQRN!) season.
I had an 80m loop at 120' for RX on 160, lower static, but not sure
if this helped or hindered receiving---only worked 2 NA stns in a 3 week
period in Apr/May '93.
300' is sort of short; I've had better luck with short wires if I
use 1 support i the middle, sort of making the wire like 1/2 a diamond.
73 de Jim, KF7E
Jim Henderson
From: john.devoldere@innet.be (John Devoldere)
Subject: Re: TopBand: Beverages
Bob:
>From this story I tend to conclude that your Beverage antenna is coupling to
your vertical. Unles the beverage is at least 60 ft prefearbly 100 ft) from
the vertical, it will pick up all the noise from the vertical, and be as
noisy as the vertical.
How close it it to your transmit antenna?
73
John, ON4UN
** de 4S7RPG - Actually the beverage is the otherside of the house from the
vertical with about 60-70 ft between them**
From: km1h@juno.com
To: <topband@contesting.com>
Date: Sat, 22 Mar 1997 14:54:04 EST
Interesting comments Bob but I suspect that you are looking for a miracle
from that very short RX antenna. At only a bit over 1/2 wave I dont know
if it even qualifies as a Beverage.
I suspect that you have a number of things working against and maybe
even for you.
1. You are using the antenna unterminated so the F/B benefit of a true
Beverage is lost and even the F/S suffers.
2. You are in a geographic area where storm induced static may be coming
from many directions.
3. The antenna is so short that it is responding to signals with a much
higher arrival angle than the TX vertical.
With that said, remember there is no magic on 160M; plus there is not a
"one size fits all" answer to receiving. Anyway, Im at least pleased that
you received the toriods OK and that something appears to be working for
you. Glad I dont need 4S7!!
73 and GL ....Carl KM1H
Subject: Re: TopBand: Beverages
Bob,
I feel part of the results from your beverage may be simply because it is
too short. If it was 450ft that would make all the difference!
I am experimenting with EWEs etc.. We should not need all this real
estate to get a few dBs gain. My 450ft beverage is around 2S. points
better than the TX antenna to the west and at least 1S. to east. Fed with
coax both ends.
It will be interesting to see if your dialogue stirrs up some activity on
the reflector.
I will go and listen now (2025)(and 21,22, etc.) and try and get
a recording of you on last night!
73's
John
G3PQA
From: eldridge@whistler.net (Bob Eldridge)
Subject: TopBand: Beverage
>... that very short RX antenna. At only a bit over 1/2 wave I dont >know if
it even qualifies as a Beverage.
Harold Beverage did not write off halfwave Wave Antennas as not qualifying.
He said "While it is possible to obtain fair directive properties with
[wave] antennas less than a half wavelength long, this length is considered
about the shortest that can be recommended".
He also said that one wavelength is the ideal length.
>.. responding to signals with a much higher arrival angle than the >TX
vertical.
Which on 160 is quite often a good thing.
Have courage Bob and keep up the good work from 4S7, especially around
1300Z. YB0ARA/9 was like gangbusters here this morning from 1246Z to 1402Z.
73 de VE7BS
From: Garry & Yelena <ni6t@scruznet.com>
Subject: Re: TopBand: Beverages
A half-wave TERMINATED Beverage has an azimuthal pattern much like a
slightly-squashed cardioid and a fairly high arrival angle on its (only)
lobe. The azimuthal beamwidth at its most useful elevation angles is
damned near 180 degrees. If unterminated, the pattern is almost
omnidirectional in azimuth and the only effective directivity is in the
elevation plane. Merely terminating it correctly as a unidirectional
antenna should provide improved performance by essentially removing most
of the rearward half of the solid angle.
My two short (too-short) two-wire Beverages fall far short of the
performance of Bevs twice as long, but they do offer a dramatic
improvement over NO Beverage. And they run through thick second-growth
redwood canyon, at ridiculous slope angles.
Garry Shapiro, NI6T
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