>>
If it was really 10-20 dB, shore locations would stand out like a sore thumb
compared to inland locations. Everyone from around New England is about the
same. Heck, K3LR is on the Ohio/PA border and does just as well or better
than coastal stations in signal levels.
<<
Hi Tom
Costal stations are not different from inland stations. There is a major
difference lost between so many e-mails and replays.
Near the water , near the beach ,or on the sand beach does not provide any
improvement on the transmit signal , the only way to see or measure this 10
to 20 db gains is ONLY with station with the radial system INSIDE de salt
water , nor near , not almost., IN.
As George AA7JV always mention it, is you have a copper plate of the size a
football field to use as ground plane where you should install your
vertical? 1 meter far from it? 10 Ft. 100m , .. well I assume we all agree
that the vertical should be on top of the copper plate.
A vertical over different ground has almost no difference on signal
intensity above 10 degree, but what happens bellow 10 degree , 5 degree
gain, 2 degree gain or 1 degree elevation gain. Well, at that point inland
vertical has almost nothing to show at 1 degree elevation angle. However
when the propagation needs only 30 t0 40 degree take off angle there is
nothing to compare.
Adding the gain on low elevation with some hops avoided during the path.
With low elevation angle the number of hops are different and the
attenuation is different as well. The perception , and here you are 100%
right, the perception on the receiver end could be 10 to 20 d.
George has been very busy with is new business lately, however I will invite
him to run some tests next month, and present here the results.
My two cents.
JC
N4IS
----- Original Message -----
From: "Michael Tope" <W4EF@dellroy.com>
To: <topband@contesting.com>
Sent: Thursday, August 14, 2014 5:03 PM
Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
> On 8/13/2014 6:28 PM, Tom W8JI wrote:
>>>
>>
>> But skimmer, which displays a relative level, does not show the level
>> difference.
>>
>> Skimmer shows about the same peak levels, but the stations closer or over
>> salt water paths (not localized salt water) have longer openings but no
>> more level for peak level. Anyone can look at that.
>>
>> K3LR is about as strong into Europe, when I look at skimmer levels, as
>> someone on the coast.
>>
>> The exceptions are people right next door to Europe (like VY1).
>>
>>
>> 73 Tom
>
> Tom,
>
> How much skimmer data did you mine before establishing a firm conclusion
> that the advantages of saltwater proximity are exaggerated?
>
> Myself, I think of how well AA7JV and HA7RY have done at various locations
> using antennas that were very close to or in some cases literally in the
> saltwater. The consistency of their topband signals compared to
> Dxpeditions who were confined to inland locations seems to point to a big
> advantage. I'll admit, however, that this hypotheses comes about from
> anecdotal observations filtered through a mental lens that is biased
> towards believing saltwater is a huge advantage.
>
> I think using skimmer is an excellent approach to this question provided
> of course that you have mined enough data to filter out the statistical
> noise.
>
> 73, Mike W4EF...................
>
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