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art wrote:
On 5 Mar, 09:59, Roy Lewallen wrote: snip Anyone who claims to have discovered principles which are beyond those incorporated in current programs has a heavy burden of proof to bear. The principle that I have discovered is not in a book but if a program is made up of proven facts of the masters proves one thing that is not ably checked by other programs based on the same facts then humasn intervention is the problem and not the principles of the masters. If one deduces an area that the masters have neglected to expand and a computor The very first hurdle to overcome in order to gain any semblance of credibility is comparison of carefully and professionally measured data with results from a carefully and professionally created model. If the differences truly are unexplainable by known deficiencies, then further investigation is surely warranted. Vague claims, speculations, and arm-waving with a total lack of any quantitative data are far short of what is needed to gain the attention of anyone who has seen, over and over, the successful results these programs routinely provide. Roy Lewallen, W7EL Computor programs made by professionals do not agree with each other so there is a problem. I would suggest that the various codes used by professionals DO agree, within their stated uncertainty limits or the constraints of the model. A simple mutual coupling approximation based on series expansion of the exponential integral for idealized dipoles will be very close to that derived from, say, a method of moments code like NEC2, but they will be different, because the underlying model is subtly different. However, a skilled user of such codes is (or should be) aware of the limitations. Likewise, you can model a vertical monopole over ground with a simple model (like assuming the ground is infinitely conducting and the monopole is infinitely thin). Or you can model it as a finite thickness monopole and a finite conductivity dielectric ground with uniform properties. Or, you can model it with the rivet heads holding the aluminum together, the dielectric guy wires, and the actual EM properties of the soil that have been determined on a 10cm grid for the surrounding km. The answers will all be different in the details, but simultaneously the answers will be the same within the limits of the approximations used. The devil is in the details of those limits, eh? Jim |