"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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