Home |
Search |
Today's Posts |
#11
![]() |
|||
|
|||
![]()
Richard Clark wrote:
On Fri, 14 Dec 2007 09:45:04 -0800, Roger wrote: Hi Richard, The math seems to work, but if you have no use for it, disregard it. On the other hand, if another perspective of electro magnetics that conforms to traditional mathematics can provide additional insight, use it. Hi Roger, This does not answer why TWO mathematics (both traditional) are needed, especially since one is clearly an approximation of the other, and yet offers no obvious advantage. I've already spoken to the hazards of approximations being elevated to proof by well-meaning, but slightly talented amateurs. The derivation did several things for me. It clearly explains why we do not have a runaway current when we first connect a voltage to a transmission line, what transmission line impedance is, that moving particles can not be the entire explanation for the electromagnetic wave (because the energy field moves much faster than the electrons), and puts into place a richer understanding of inductance. I am surprised at your criticism in using DC. To me, a square wave is DC for a short time period. This single statement, alone, is enough to be self-negating. You could as easily call a car with a standard stick shift an automatic between the times you use the clutch - but that won't sell cars, will it? We could use the concept of a stepped wave, but that would imply the need for several steps to develop the formula. Only the square wave front and continued charge maintenance is required, observations that can be easily verified by experiment. Is the observation that a square wave can be described as a series of sine waves troubling to you? Perhaps the observation that a square wave might include waves of a frequency so high that they would not be confined in a normal transmission line is surprising or troubling to you? DC as sine waves is not a contradiction on the face of it? DC that consists of waves of a frequency so high that it would not be confined in a normal transmission line is very surprising, isn't it? What is your point here? Are implying that the formula is incorrect because a sine wave was not mentioned in the derivation. I am sure that all of the sophisticated readers of this news group understand that the sharp corner of the square wave is composed of ever higher frequency waves. This leads Cecil to comment that the leading edge of a square wave could be composed of photons, which is a valid observation. It also explains your observation that true square waves are not possible (I am paraphrasing your comments) because of dispersion. It is interesting to run an FFT on a square wave to see how the frequencies can be resolved. Would it surprise you to find your batteries in their packaging direct from the store are radiating on the shelf? They are DC, are they not? If the arguments of your sources works for an infinite line, they must be equally true for an infinitesimal open line. When your headlights are on, do they set off radar detectors in cars nearby because of the high frequencies now associated with DC? They only set off the radar detectors when I turn them on and off. I have high power lights!! A lightning strike is a much better example of DC containing high frequencies. My goal is to better understand electromagnetic phenomena. You have given some very astute insight many times in the past and thanks for that. Negative comment is equally valuable, but sometimes a little harder to swallow. The pollution of terms such as DC to serve a metaphor that replaces conventional line mechanics is too shallow glass to attempt to quench any thirst. The puzzle here is the insistence on hugging DC, when every element of all of your links could as easily substitute Stepped Wave and remove objections. The snake in the wood pile is once having fudged what DC means, it is only a sideways argument away from rendering the term DC useless. Is the term Stepped Wave (the convention) anathema for a leveraging the novel origination (the invention) of DC Wave? 73's Richard Clark, KB7QHC We would complicate the concept and thereby begin to confuse people if we insisted on using the "Stepped Wave" term. It is a simple step to recognize that if we can make a wave front with one battery, we can use a lot of batteries and carefully place and switch them to form a sine wave. The more batteries and switches, the better the representation. Is there some harm in considering Zo = 1/cC? It should only add to the tools we have to explain electromagnetic waves. 73, Roger, W7WKB |
Thread Tools | Search this Thread |
Display Modes | |
|
|