Hi Jon,
This is a topic I'm interested in, having used phased loops and Beverages
since the early 70's at all my locations.
In a message dated 96-03-19 03:02:35 EST, you write:
>A 3 or 4-wavelength beverage (1800-2400 feet on 160) gives you a low
>take-off angle (15 degrees for 4 wavelengths) and fairly narrow beamwidth
>(about 40 degrees for the 3 db-down points0. Longer beverages will only
>slightly more narrow the beamwidth and only slightly lower peak wave angles.
I wonder if that data is from NEC models?
My experience agrees with your conclusion, a long Beverage is not only not
worth the effort...it can actually be worse. But I attribute it to loss in
the element more than changed wave angle. When I measure (with a real meter)
current distribution, more than 50% of the current is gone after 500 feet
over some soils! The best situation I measured was in a Marsh type soil, with
25% current loss.
That's 2.3 to 6 dB loss per 500 feet. Adding extra length to the antenna when
loss is that high CAN'T make reception better, since the far end doesn't
contribute useful signal levels. John Kuecklin, in actual measurements,
showed the gain of LW's actually goes down when the wire is made too long.
I wonder if I can get someone else to excite their antenna with RF and make
the measurement? But anyway, my conclusions about results are the same as
Jon's.
>At times 3-4 wavelengths will be too long because propagation is favoring
>high-angles. WB3GCG developed a relay system to break up an 1800-ft beverage
>into shorter lenghts of 600 and 1200 ft
What did Wild Willy notice?
At all my past locations, four phase in line loops were better than any
Beverage, and at the quiet locations a Beverage was only ~3 dB better than a
simple vertical. An EWE is useless here, unless I installed a large ground
screen under it. Then it's still poorer than the Beverage.
Ernie, K1PBW all but abandoned Beverages when he had TWO verticals phased. He
said they were much better than the Beverage. At WXEZ where I had a dipole up
330 ft, the Beverages were useless in comparison. I think the answer "how
much benefit is it?" varies with location. It sure does with the EWE's.
73, Tom
>From Ham <batchler@fsac3.pica.army.mil> Tue Mar 19 13:46:44 1996
From: Ham <batchler@fsac3.pica.army.mil> (Ham)
Subject: DXpedition
Message-ID: <9603190846.aa07090@FSAC3.PICA.ARMY.MIL>
Hi gang I'm going to Hawaii for vacation-also WPX contest
look for KB3TS/NH6 will be multi-single with my son Tim N3KEG/KH6.
73 aloha Laing
Please all remarks/replies/comments to
batchler@pica.army.mil
fax 201-724-5768
Laing Batchler KB3TS - F.R.C.
>From emoody@epix.net (Ed Moody) Tue Mar 19 17:26:05 1996
From: emoody@epix.net (Ed Moody) (Ed Moody)
Subject: Dxpeditions for Contests
Message-ID: <Chameleon.960319092920.emoody@EPIX.NET>
Time for me to get my two cents in. Been doing
CQWW contest DXpeditions for 15 years. We are
best known as PJ1B (hear all about it in Dayton).
Nobody, and I emphasize NOBODY (including any
Radio Club) has ever donated, kicked in, or
otherwise financially assisted any of our contest
efforts. We have never even had a piece of
equipment donated. This effort has not been by
wealthy "fat cats" but by a bunch of hams who
just want to bring another multiplier to the
contest and make it interesting for everybody.
73-ED, N3ED
>From Matthew S. Trott" <0007288678@mcimail.com Tue Mar 19 14:43:00 1996
From: Matthew S. Trott" <0007288678@mcimail.com (Matthew S. Trott)
Subject: KT34XA (Wind Balance)
Message-ID: <85960319144358/0007288678PJ4EM@MCIMAIL.COM>
Yo, What's the tried and true recipe for wind balancing a KT34XA? Or is it
already pretty well balanced? Does anyone have the torque element dimensions
and boom placement for this antenna? Or is boom extension the answer?
This info may already be on FOX www site but alas, I don't have web access at
present. I appreciate any info.
73--Matt--AA7BG
aa7bg@mcimail.com
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