Home |
Search |
Today's Posts |
|
#1
![]() |
|||
|
|||
![]()
Art:
[snip] Frankly I don't see that 'What" term in my books or in the newespapers so I presume it must be a Cajun type dielect that is used in the swamps or something. You used it a lot when you ran Chip off the group but since I don't know what you are talking about I will stay on even tho Ian and Roy have now fled. Art [snip] Heh, heh... Well, I got the term "What?" and that particular usage from my then... teenage sons, both now in their mid-thirties, but no grandchildren, What? "Cajun", heh, heh... Hey... I was born in the "real" Acadia [Nova Scotia] and so was formerly a British Subject. I left for the "colonies" lo these many years ago and I am no longer taxed without representation. Since I immigrated, I have always lived in the "Deep South". I have been to "Luzianne" and "Nawlins" often and I have many Cajun friends. I have been properly introduced to "crab boils", "pulled pork" and the pleasures of cayenne pepper and "crawdads". But... I have never "run off" any real persons, only pretentious, oafs flouting advanced University degrees! Best Regards, -- Peter K1PO |
#2
![]() |
|||
|
|||
![]()
But Peter you said something about changing a model
What was that all about ? Regards Art "Peter O. Brackett" wrote in message ink.net... Art: [snip] Frankly I don't see that 'What" term in my books or in the newespapers so I presume it must be a Cajun type dielect that is used in the swamps or something. You used it a lot when you ran Chip off the group but since I don't know what you are talking about I will stay on even tho Ian and Roy have now fled. Art [snip] Heh, heh... Well, I got the term "What?" and that particular usage from my then... teenage sons, both now in their mid-thirties, but no grandchildren, What? "Cajun", heh, heh... Hey... I was born in the "real" Acadia [Nova Scotia] and so was formerly a British Subject. I left for the "colonies" lo these many years ago and I am no longer taxed without representation. Since I immigrated, I have always lived in the "Deep South". I have been to "Luzianne" and "Nawlins" often and I have many Cajun friends. I have been properly introduced to "crab boils", "pulled pork" and the pleasures of cayenne pepper and "crawdads". But... I have never "run off" any real persons, only pretentious, oafs flouting advanced University degrees! Best Regards, |
#3
![]() |
|||
|
|||
![]()
Art:
[snip] "Art Unwin KB9MZ" wrote in message m... But Peter you said something about changing a model What was that all about ? Regards Art [snip] What I meant is that there is the "real world" and its' behaviour as evidenced by experiment and measurement and then there are "models" , i.e. theories or mathematical constructs which humans have devised to "imitate" or "model" the "real world". When considering accuracy and precision whenrepresenting real experiments and measurements models that attempt to reflect real world performance over time have come in various stripes. In the history of electro-dynamics there have been three major models/theories developed in three eras over the last couple of hundred years. (I) Circuit-Theoretic Model Era (circa: 1750 - 1850): The first model/theory of electro-dynamics was the "circuit-theoetic" model which used the circuit theory of Messers Kirchoff and Ohm, developed in the late 1700's and the early part of the 1800's . Kirchoff's Laws and Ohm's Laws for DC circuits ultimately supported by Heaviside's operational calculus in the mid 1800's to reflect both DC and AC phenomena. [Heaviside invented the terms reactance, and impedance, etc.] But experimentalists and the "electricians" of the day found that circuit theory models did not predict everything exactly! All that said, the circuit-theoretic electro-dynamic model is pretty simple and accessible to anyone with a modicum of mathematical background, say the equivalent of high school algebra and complex numbers. Sorry... but if you can't do simple algebra, deal with the square root of minus one, and manipulate complex numbers then circuit-theoretic models are not your cup of tea. Get off the train here and go into marketing or the social sciences! :-) Circuit theory does a pretty good job of predicting lots of things, but it fails to predict effects such as skin effect, proximity effect, radiation, etc... And so the electro-dynamic model was eventually augmented by a newer model which was more accurate reflects reality more closely. The second stage of the three eras of electro-dynamic theories was the: (II) Field-Theoretic Model Era (circa: 1840 - 1910): The "field-theoretic" model was first formulated the famous Scottish theoretical physicist James Clerk Maxwell, and rendered in its' modern form by the eccentric, uneducated, self-taught English genius Oliver Heaviside. Heaviside wrote down Maxwell's extremely complex theory in the form of four simple vector differential equations as we now know them. Whilst previously it had taken the Cambridge educated Maxwell 22 quaternion laced equations to write down the same simple theory! Heh, heh... Of course Heaviside, a denzien of the London slums, who never went to school beyond age 16, had the advantage of "simplicity-of-thought" over the Cambridge educated Maxwell. All that said, the field-theoretic model is considerably more complicated than the circuit-theoretic model and is only accessible to those prepared to go beyond high school algebra and complex numbers into the calculus of vector differential equations. Sorry but if you are not prepared to go there, as the sixteen year old poor boy from the slums of mid 1800's London did, then field-theoretic modeling is not your cup of tea, and you need to go into marketing or the social sciences... :-) Field theory is more complicated than circuit theory but it does a pretty good job of predicting all that circuit theory predicts plus a lot of other things, such as skin effect, proximity effect, radiation, etc... but even field theory fails to predict the photo-electric effect, and other interactions of photonic energy and matter, etc... And so the electro-dynamic model had to be expanded yet again, this third (and final) theory is called QED or Quantum Electrodynamics. (III) Quantum-Theoretic Model Era a.k.a. QED (circa: 1900 - 2000) The quantum-theoretic model was initiated by Einstein in the first decade of the 1900's to explain the photoelectric effect and was further developed by Pauli, Dirac, Schrodinger, Planck, and many others and ultimately "simplified", in the Oliver Heaviside style, by one Richard P. Feynman from the Bronx, NY who also dramatically exposed the cause of the Challenger tragedy with a glass of ice water. For these efforts "Albert" was awarded the Nobel prize. One can only presume that the Nobel committee did not feel that the Theory of Relativity a.k.a the "Ultimate Theory of Gravitation", was worth the prize! Although they did award the prize to that Italian ham radio operator Guglielmo Marconi! What? :-) Now the mathematics needed to access QED is considerably more complex than that needed for circuit theory (Algebra and Complex Numbers), field theory (Algebra and Complex Numbers plus Vector Calculus and Vector Differential Equations). Indeed to access QED models one needs to understand all of the aforementioned plus the mathematical Theory of Probability and the Theory of Groups, Rings and Ideals. If you are not prepared to go there, as that poor boy named "Richard" from the Bronx was, why then QED is not your cup of tea and you should get off the model train now and take up marketing or the social sciences... :-) It seems today that QED models encompass all prior models and fully explain all known electro-dynamic phenomena and that mankind does not require further models to augment those at hand to predict electrodynamic reality. I wonder? All that said... this does not mean that QED has displaced field-theoretic and circuit-theoretic concepts and models. Indeed circuit-theroretic and field-theoretic models are more widely used today than ever before! Indeed circuit-theoretic models and field-theoretic models are used daily by Engineers and scientists (Note the capitalization!) on a daily basis. [Engineers make things people need out of stuff they can get, while scientists... :-)] Indeed the mathematics and mechanisms of QED and field-theory are much to complicated and unecessary to make efficient modeling of phenomena that are quite adequately described by circuit theory. Hence the very popular SPICE computer programs, originally developed, with US Taxpayer support, at UC Berkeley in California and widely available for free download, which are used everywhere today to design both discrete and integrated electronic circuits from modern Op-Amps to Pentium processors uses the century and a half old circuit-theoretic models. For an excellent free version of SPICE download LTSpice from the Linear Technology Corp. web site at: http://www.linear.com/software/ and run circuit-theoretic models to your heart's content, just don't use SPICE codes to design antennas or predict the skin effect! :-) Oliver Heaviside would quickly recognize the SPICE program flow charts and computer codes were he alive today! But circuit theory is not complex enough to solve antenna and radiation problems or skin and proximity effects and so one needs access to models and computer programs that solve the partial differential vector equations of the Maxwell-Heaviside field theory. Hence the very popular, US Taxpayer supported, NEC computer program codes were developed at Lawrence Livermore Labs, also available as free downloads. Our own Roy Lewallen W7EL provides his EZNEC programs based upon the free NEC codes for a modest fee. Download Roy's free demo of EZNEC at: http://www.eznec.com/index.shtml and run field-theoretic models to your heart's content, just don't use it to design photoelectric sensors or Pentium processors! ;-) Finally if you really need to go there... There are plenty of QED computer programs available, also widely supported by the US Taxpayers, just google... An Engineer is a person who knows reality and knows her models, and she... "knows whento hold them and when to fold them". She uses them to design and build things that people need out of stuff that she can get. Don't forget to thank the, often vilified, US Taxpayers for their unwavering support of the development of all of the free computer program implementations of circuit-theoretic, field-theoretic and QED models with the computer programs called SPICE, NEC and other QED kinda stuff... Happy Holidays, y'all! -- Peter K1PO Indialantic By-the-Sea, FL Hey... "surf's up"! |
#4
![]() |
|||
|
|||
![]()
Peter,
I have read your posting again and again without commic thoughts to the term 'What' and I have no intention of following 'Doc" I do see that you are educated as I believe I am, tho I am not a Doctor. But where you and I differ is in philosophy. One can become educated by following the crowd and concentrate on what is necessary to pass the exam. By the same token one can do the same but place attention to what is pushed aside as being inconsequential in terms of general useage ans inductance pretty much fits into that bracket, whereas even the inconsequental information is also pursued by the inquisitive. To make money in life one can push aside what is inconsequential but if you are inquisitive it is often the study of what is placed on the cutting room floor that provides inovation, the latter is what I do. Now let us consider my model and since you are educated I can cut some corners. When looking at antennas current is everything so that is where inovation starts. An examle where current can be changed is a simple transformere. It has two seperate circuits and it satisfies lawas of E = I R ( add cos phi if you want to )but what it does do that one doesn't normally thing off is to add the function of coupling. Link coupling when coils are wound on top of each other or proximity coupling when wound on separate bobbins. So thinking outside of the box we have a model that matches its power input, has two circuits that are connected and suplies a means for high current flow. All of this is down to COUPLING.... Now this tyransformer model provides exactly what the World requires of an antenna and pushes aside physical dimensions such as wavelength, radials e.t.c. I know ...there is nothing new..... Now apply that same thinking to the subject of antennas. We have an equivalent item that we use for matching purposes and that is a pi network. Now we have the means of providing matching to an antenna with capacitance etc. to provide an output but remember what we called inconsequential about lumped items which are really attempts to remove what we originally disliked ala coupled networks. By coupling circuits ( networks) we can maintain ideal input matching, increase current into a desired circuit and because it is a circuit it will radiate. And do it very well with high efficiency as well as meeting the reqirement for high radiation by virtue of the increased current. Now this model or way of thought is new but it is a different application of the known that is considered inconsequential and thus is not seen in books that is written for crowd followers. Should one discard a model just because it is not in a book ? Not if you are inquisitive, you then make such a system that has all these desirably qualities and enjoy your efforts while others who rely only on books or exercise their mouths poke fun because to them it is unknown. I HAVE THAT ANTENNA AND IT WORKS EXACTLY CCORDING TO KNOWN THEORY you are welcome to point out any fallacies as why it shouldn't or can't work as I believe it is the new horizon for antennas and experimental work. Regards Art |