All,I am not very educated in these matters so I have nothing specific to add
other than this: 1-We have some really bright "friends" who share the love of
this exciting Hobby. And a true friend will freely share his perceptions,
whether popular or not.2-Our individual perceptions differ almost
infinitely.3-Amost all our derived Laws of Physics are considered absolute, but
even a miniscule few are subject to change as we gain accepted knowledge as
Homo Sapiens.4-Anecdotal observations may occasionally stimulate those who
possess a wealth of scientific knowledge to look for possibilities. That brain
can be a superior tool to reject subjective fantasy and emotion from scientific
possibility. 200 years ago, scientific minds didn't possess infinite
knowledge. New Axioms emerged.The same is true today.5-My 9th grade math
teacher said "Two heads are better than one, even if one is a Goat Head."
Sounds stupid, but he was talking about solving math problems. True.6-It has
been sa
id..."The Ionosphere is a great equalizer of signals". I translate that to
mean, as much as we know, there are some more things to learn in order to
explain what we experience with signals.7-I have enjoyed several locations and
setups, from meager Novice days with a poorly matched 300 ohm piece of TV Twin
lead lying on a shingle roof, to the highest hilltop in Gwinnett County, Ga to
9 Towers on 23 Flat Acres, to a restricted community where I have very poor
wire antennas, but in/over Salt water and very little noise. I have my stories.
In general they parallel what we unschooled accept from those who are our
mentors. 8-I am owing to my friends of my almost 60 year career who have
shared both anecdotal and scientific help to supplement my trial-and-error Ham
Radio escapades. What I lack in foundation I possess great resolve.9-I do not
claim to be the first, I don't know who first designed one, but I may have
stumbled upon the first Half Sloper in 1973 just because I wante
d to get up an antenna for 80M and used 65' of #26 magnet wire direct fed
against a 90' tower with some Log-yagis on top. I did not know if or why this
would or would not work. I just tried anything that seemed reasonable. This
was a lucky point which matched...I did not know where to start. The same for
a side mount rotor...I HAD TO. I wanted another Yagi, but no room for another
tower. A welder at a Filling Station built my design in 1973. I was a
Dentist, not a mechanical engineer.10-We need each other. Hams dedicated to
scientific knowledge, those willing to share personal experiences-no matter how
flawed the principle seems, experimenters, those who are brave enough to
unselfishly sharing their vast base of information, those who risk telling us
our perception is skewed against Physics, those who use all these experiences
to further our enjoyment of this great hobby by designing circuits we use
daily....whether for profit or just plain sharing. We can all add s
omething to be accepted or rejected. Relative to what I should know as I
continue to explore DX, I do know and accept that I am a Goat Head. But thanks
to all who contribute, whatever their intention or level of skill and
knowledge. Keep posting. 73, ValN4RJ Whatever it is, there IS something magic
to Salt Water and Hill Top locations. Both have different but magnificent
effects on propagation. The VP2KC location had both, I have been spoiled
beyond repair. I am a Ham-O-Holic and am proud of it.
---------- Original Message ----------
From: Tim Shoppa <tshoppa@gmail.com>
To: Guy Olinger K2AV <k2av.guy@gmail.com>
Cc: TopBand List <topband@contesting.com>
Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
Date: Thu, 14 Aug 2014 08:49:32 -0400
"Vertical on a beach" DXpeditions have a very different mindset about
choosing operating hours and greyline openings, than other kinds of
DXpeditions.
Often they are also away from the RFI sources that are increasingly present
even off the mainland.
It should not be surprising that, over and above whatever propagation
advantages, the right mindset and operating choices work to the advantage
of us lowband operators trying to work the DX :-)
Tim N3QE
On Wed, Aug 13, 2014 at 4:54 PM, Guy Olinger K2AV <k2av.guy@gmail.com>
wrote:
> > One would think if there was a 10-20 db penalty, it would show on
> skimmers
> > and that W2GD would be unbeatable being on the water. I'm sure I'm
> missing
> > something. What is it I am missing?
>
> A contest certainly is not only about transmit signal strength, nor is
> the lowest angle propagation always the most productive. There is
> always the 27 dB gain between the operator's ears (or lack of it) to
> be reckoned with. But usually a station in the contest that shows up
> when the shore emphasizes the low angle before full band opening will
> usually be there when the band opens with higher angles less
> emphasized by the water's edge. A top station inland may not be able
> to work him until a half hour later, but if the DX is working the
> contest, a top station WILL work him, removing the scoring benefit
> from the shore station's propagation advantage.
>
> To win a contest one still has to vacuum out the bands of any little
> ole signal that pops up and has to manage 360 degrees of horizon worth
> of contact opportunity. Even so, on 160m tests, the consistent
> placement of W2GD and K3ZM, particularly K3ZM, in the top few or
> outright winning over the years points to SOME persistent advantage,
> despite competition around the country with commercial grade stations
> and despite inland station staffing with certain clarion absolutely
> excellent operators.
>
> Some beach DXpeditons had the advantage of a location where nearly all
> their contact opportunity, by the numbers or by the multipliers, was
> across the salt water. That's basically not true for anyone in the US,
> which reduces any water's edge advantage for a US station. But the
> DXpeditions that had 95% of stuff across salt water from the edge
> certainly did clean up, even with the 12 dB handicap of 100 watts TX.
>
> As to the signal level contrast driving away from the beach, the
> inland soil is commonly very sandy, and particularly when wet is about
> as lossy earth as might be found. There is a not-at-all unreasonable
> case to be made for the idea that going from water's edge some
> hundreds of yards inland is going from sublime "ground
> characteristics" over salt water to brutally ugly "ground
> characteristics" over damp salt-tainted sand. Once those details are
> in, the one or two S-unit difference reports from people driving
> around the beach are not so unreasonable.
>
> The other comparison to be made is that antennas over water's edge are
> frequently verticals, out of construction necessity. The proper
> comparison of a 40m vertical at salt water edge would be to a 1/4 wave
> vertical close to ground somewhere out in the W3LPL meadow, not to his
> full-sized stacked yagis on a 200' tower. IMHO a meadow vertical at
> W3LPL would be incredibly crappy vs. the same at salt water edge,
> easily exceeding two S units in that period where only the lowest
> angle signals are peeping through and the band isn't quite yet open.
>
> A warning to ourselves, denigrating and ridiculing ALL anecdota, in
> the end, is just as unreasonable as swallowing it all without careful
> sorting. It's going to be a tough time introducing progress if
> non-owners of FIM-41 commercial MF field strength meters are always
> assumed either idiots or bold-faced liars in their reports. A lot of
> great food in the world, when raw, is unsavory, repugnant or even
> poisonous before being processed into something delicious and
> nutritious. We just need to be PROCESSING anecdota.
>
> 73, Guy K2AV
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