I think that what is being suggested is, that if you have two signals, one
S9 and the other right at noise level. The salt water advantage shows up
more on the weak signal. Let us say both increase by 6db the S9 signal won't
be noticed as louder, but the weak signal will now show clearly above the
noise, just like turning on a light. Even though BOTH have improved by 6db.
73 Clive GM3POI ( by The Sea)
-----Original Message-----
From: Topband [mailto:topband-bounces@contesting.com] On Behalf Of Tom W8JI
Sent: 15 August 2014 12:10
To: Guy Olinger K2AV
Cc: TopBand List; Guy Olinger K2AV
Subject: Re: Topband: Modeling the proverbial "vertical on a beach"
> The signals showing the most change were not the loudest. They were
> the ones on the edge of the developing band opening. The stronger or
> peak signals from these stations would occur later as (presumably) the
> angle of arrival moved up. The advantage to the water's edge I was
> hearing would only last from first hearing to full band opening. To
> the extent that the opening was very marginal, the advantage could
> persist.
>
One of the big things in any experiment is to think about all the factors
that can cause a feeling or impression, and just look at the meaningful
numbers.
1.) If you had a non-linear effect based on loss it was probably the common
effect of small changes in threshold signals being most noticeable. This
effect is just a fact of life. We see it without realizing it. Linear loss,
and we know the loss is linear with level, change weak signals exactly the
same as strong signals. They change noise exactly the same as signals.
2.) If you were observing a wave angle effect, you would have had to sort
the signals by wave angle. The irony of this is the most vocal advocates of
high angle propagation, where salt water has no advantage (except a small
one on bounce) over a localized very modest copper screen, are the same
people who claim enhancement.
All of this is measureable if we do a correct and reasonable test. It is not
measureable or observable with poor methods, or by human emotionometers.
It is, on the surface, illogical to claim weak signals are changed in a way
that does not occur on stronger signals. Nowhere in anything except
non-linear circuits will that occur.
When people come up with numbers or observations exceeding the change
possible by moving an antenna from over soil to over an infinite copper
sheet, or invoke some sort of non-linearity based on level, something is
obviously wrong with the observation or reporting.
73 Tom
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