Tom,
I only have about 491 ft of window line and thats what I am using for the two
direction beverage. Placement is in part dictated by the hill but mostly the
rationalle
for the 300 or so feet from the inverted L is that it has a lot of noise. It
is terrible actually
much of which is due to the McMansions they built in the farmers field next to
me.. UGH!
I didnt realize how good I had it. .. you know the ones.. they have several
large screen
plasma TVs and loud parties during football, baseball, hockey and basketball
season.
Geeze thats just about all year of interference.
ANyhow over the last 5 years it has gotten progressively worse. I dont want to
take a chance
on ANY noise being picked up on the beverage and I thought that the hill would
be a nice
natural barrier and it just happens to be about 300 ft away.
Hummmmm I wonder .. leme see can I paint a target on the side of their houses
and call in a
JDAM strike to get rid of the noise.. OHH NO cant .. sorry thinking out loud
again.
Seriously.. it is all about mitigating as much noise as possible.
Thanks to all of those that responded with encouragement during this effort.
Jim WA3MEJ
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Message: 1
Date: Thu, 17 Nov 2011 02:11:52 -0500
From: "Tom McAlee" <tom@klient.com>
Subject: Re: Topband: Location of beverage close to 60 ft hill
To: <topband@contesting.com>
Message-ID: <09bf01cca4f8$31e41e60$95ac5b20$@com>
Content-Type: text/plain; charset="UTF-8"
Go for it. I live in the middle of the Appalachians and my Beverage wires go
up and down many hills and valleys and cross many ravines and work great. On
their worst day they still hear things my TX vertical couldn't hear on its best
day :)
> Comments Please
1. Why the need to keep it 300' from the inverted L? You can read a lot about
how they should be far apart, but (outside of multiband contest stations where
one radio is trying to listen on the Beverage while another is transmitting) it
may not be so important in practice. I will explain my experience...
A few years ago I put up 580' Beverage antennas for NW, NE, SE, and SW. I read
that they should be far from the TX antennas, so the closest point from any of
those RX antennas to any TX antenna is about 1000'.
To cover the "missing" directions, I put up a 4 square receive antenna from a
popular manufacturer. But, I found that the Beverage antennas were (usually,
but not ALWAYS) better than the 4 square even in its favored directions. So, I
decided to put up Beverages for N, E, S, and W also.
N and S were no problem. But, when it came to E and W there was an issue. All
of my Beverage antennas are installed on my neighbors property. It is 32 acres
(surrounded east through west by 1.6 million acres of national forest!) but
very "long". It is about 400' wide by about 3200' long with an odd triangle
shape at the far end, all pointed slightly northwest. I am on the west side of
that property.
A 580' East/West Beverage would just not fit on his property unless I put it in
that odd triangle area at the end, which was about 2500' from my house!
Alternatively, I could put it in the area where his property and my property
lined up. That would give me 800' E/W to work with, but it would mean that the
Beverage would come within 100' of my TX vertical (and the miles upon miles of
radial wires that lay on/in the ground around them).
I consulted my friend and antenna mentor Frank, W3LPL. Frank suggested that I
first put up the E/W Beverage where it was close to the TX vertical. If the
noise wasn't any louder than it was on the other 6 Beverage directions it was
fine. Otherwise, he recommended going the 2500' away route.
I did as he suggested and it turned out to be just fine. My E/W Beverage,
which runs within 100' of my 160m TX vertical and 80m vertical array, doesn't
have any more noise than the other 6 directions whose combined closest point is
1000' away from the TX antennas (the furthest points are much further!) The
S/N ratio on the E/W antenna is not discernibly different than the other 6
directions.
If I were a multi-band (multi/multi or SO2R) contest station I suspect I would
have issues trying to listen on that antenna while transmitting. But, for
DXing purposes, it works very well.
It is worth noting that this antenna merely "passes by" one or more TX
verticals within 100'; the feedpoint is several hundred feet from any TX
vertical and doesn't line up with the base of any TX vertical in a targeted
direction.
2. You said your target was EU and AF. I have found (from southwestern VA
where the bearings aren't much different than they are in MD) that an EU
Beverage and an AF Beverage are two different antennas. At least with 580'
antennas, 45 degrees is great to EU and northern AF while 90 degrees is great
to central/southern AF (and ok to northern AF). A 580' Beverage pointed at EU
won't hear central and south AF very well. If you can do two, I'd recommend
one at 45 degrees and one at 90 degrees. If not, I'd recommend one at 60
degrees.
73,
Tom NI1N
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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