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Old 19-11-2006, 12:31   #31
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John-
I suspect that the real reason so much of "THE LITERATURE" conflicts is simply that when all is said and done, we are dogs looking at elevators. Huh?

You know, a dog gets in the elevator, gets out of the elevator, ooh, look at that, the universe outside changed. And the dog has no idea how or why, but he knows that elevator CAN change the universe.

Someone out there might understand why radio signals really work, and why there are different components of them, and whether there is aetherial fluid or charmed quarks or strings, particles, or waves (pick your advnaced physics of the month<G>) but as best I can figure it, no one has ever written and proven a solid theory of how this stuff really works, in simple enough terms to put it on one page, in simple words.

The rest, is the observations of many dogs on many elevators. They can describe a lot of what happens, but it often isn't quite on the mark. The practical stuff (like trying to use only one ground point, to prevent ground loops, or what antennas *usually* work) passes for fact, often enough to work.<G>
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Old 19-11-2006, 16:02   #32
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"The Literature"

"The literature" of which John speaks is not scientific literature it is the usual semi-rigorous-almost-technically-valid print that appears in boating mags attempting to explain in "simple terms" to people without technical backgrounds a means of how one can get the job done. Technical literature DOES and HAS for some time now explained not only how electromagnetic waves propogate but how various structures affect the propogation. The math is not simple and, therefore, cannot be simply explained. There are, in fact, some advanced programs capable of modeling particular yacht structures capable of accurately predicting the transmission and reception capability of a "matress spring" attached to a tuner output with various rigging and pulpit metal around.

Just because a "simple" explaination has not been published that everyone can understand does not mean that a solid theory does not exist and is not valid. You cannot believe the development in antenna design using such theory and modeling capability that has allowed significant advances in all areas of electromagnetic design from just above dc to "daylight" frequency applications. One wonderful example is your GPS antenna/receiver which is today fairly integrated and continues to be improved upon. These designs could not have been realized without a solid understanding of the existing theories related to electromagnetism and wave propogation.

There are, and have been, some simple explanations in some of these threads regarding the theory and reality of ground (and "power") loops that most non-technical people can understand. The same explanation is part, if not parcel, to the reason that single point rf "grounding" should be used, if possible. Yes, there may be valid reasons to use multiple ones in different designs and applications.

One point that I keep hammering out in this arena regarding the high-frequency band of antenna "grounding" is that the word counterpoise does not apply for small yachts due to the sheer dimension required to accomplish a real counterpoise phenomenon. Whatever meager attempts are made to run foils, grids, etc. beneath and in the vicinity of, a "quarter wave" radiator accomplish some coupling to the water beneath and around the hull via capacitive (and even inductive) coupling, NOT by creating an actual electromagnetic "mirror" for the radiator to function as a quarter- wave-with-ground true counterpoise. Making a direct connection from a tuner "ground" point to the water in a reasonably short(electromagnetically short for a given frequency) vertical direction makes the best "ground" if reasonably realizable. This is why the really effective HF antenna sites have been located on huge flat areas over salty moist areas. I used to work at a couple of such sites where making HF counterpoises work the best at 2 to 4 MHz was always enhanced (if used at all) by such earth characteristics beneath.
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Old 20-11-2006, 09:24   #33
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Rick-
"Technical literature DOES and HAS for some time now explained not only how electromagnetic waves propogate but" Does it? I know it describes the propogation, but does the literature to date yet explain how the actual interaction on the sub-atomic level happens? Or whether this involves waves, particles, string theory, or religion [wink] yet?
What about that guy at RISD who patented a supposedly radical new antenna design last year? What about the folks at Brookhaven who did something terribly odd a decade ago, something like splitting a particle and then watching how one half, physically separate and isolated, responded to motions on the other half? i.e. Rotate one of the particles, and the second one rotated as if they were still attached--despite being fully separated and isolated according to all the "rules" of modern science.
This is what I mean by allthe literature not explaining things. We know apples fall from trees--but if we knew what gravity really *was*, we could be doing a lot more with it. Ditto for radio. Describing the symptoms and reactions as it passes through the universe, to me that's not really understanding it. That's just observing the way it usually passes.
Kinda like the way the speed of light drops to literally 30 miles per hour in a Bose-Einstein condensate (the fifth state of matter). There have been some freaky things reported about experiments with light now too--like getting the speed down to zero, or even negative numbers, if you believe some of the results.
From my point of view, I can deal with being the dog at the elevator. I know that sooner or later, the view out the elevator door is gonna change. With or without my help, just need to be patient.<G>
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Old 20-11-2006, 12:10   #34
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valid explanation and "knowing"

Aaaah, now I understand what you are pointing out here, although that tends to add fuel to the fiery zeal in those who hypocrites who delight in degrading science and technology whilst they enjoy the results therof. Your point of view is what I call that of the philosophical theoretical physicist whereas I am a practical engineer who merely delights in using the scientific method and critical thinking to solve a problem in the real world with what is at "hand".

It is the known and accepted body of knowledge proven to work within specified parameters that provides no-bull methods for such problem solving that I am refering to here. I am not waving my arms around pointing to some far-strung pseudo-science like the Testla freaks who think that one can tap into an energy node located in some specific place in free space to generate free energy.

Yet, no, I do not claim to really "know" just how electromagnetism works any more than I "know" just how my woman "feels" inside as she requests my sensitivity towards some emotional problem. I cannot know because it is unknowable. Yes, I AM interested yet realize my limitations in not being able to really "know" anything other than the existential reality of "I feel, therefore, I AM". Ultimately such is the reality of physics in not REALLY ever being able to "know" or truly understand anything with complete validity, at least existentially. Eh?
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