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Standing-Wave Current vs Traveling-Wave Current
Roy Lewallen wrote:
Roger wrote: I see your example as identical to Keith's example of two wave pulses traveling in opposite directions. Not quite. The voltage following a pulse is zero; with my sine wave example the source continues producing a sine wave at all times while wave interaction is occurring. At the point of interaction, Keith's example has a reflection factor of 1 or zero, depending upon whether the waves bounce or pass. Keith's example is not a short circuit because two pulses of identical polarity are interacting so a reflection factor of -1 could never exist. Because there are no mathematics and, as far as I can see, no mechanism for wave interaction, I can't discuss Keith's example except from the standpoint that the waves don't interact. (Excluding, of course, superposition from the meaning of "interact".) In your example, the presence of voltage from the ideal source creates conditions identical to Keith's example for the returning reflected wave. Accepting this premise, then the reflection factor must be either 1 or zero, depending upon whether the waves bounce or pass. Sorry, I don't accept the premise. By assuming that the waves reflect at the ideal source, you proved that the reflection factor is -1, which is the factor for a short circuit. Yes, that is correct. This can not be the case, so waves must not reflect at the ideal voltage source, they must pass. Well, yes it can be the case, and is. But let's see where rejection of this fact leads. vtot(t, 0) = vf(t, 0) + vr(t, 0) = sin(wt)tot = sin(wt) + sin(wt) = 2*sin(wt) Someone will certainly say the the vtot(t,0) at the source location is the source voltage, because it is defined that way. I certainly say that. The conditions at point (t,0) itself is actually unknown (because vf mysteriously appears, and vr disappears by going off the transmission line), but point (t, 0) is defined by assumptions. Therefore, at vtot(t, 0) = vf(t, 0) + vr(t, 0) = sin(wt)tot = sin(wt) + sin(wt) = 2*sin(wt) So by rejecting the fact that the waves reflect at the ideal source, you're forced to conclude that the voltage at the output of a perfect source is unknown, with waves "mysteriously" appearing and disappearing. It also appears that you've violated Kirchoff's voltage law at the input. My analysis requires no such contradictions, unknown voltages, or mysteries. As an engineer, I like my analysis a whole lot better, because it can give me answers which are testably correct. Can you use your theory to show the voltage at all times at the input or, if you choose, just inside the input of the line, as I've done using conventional theory? Yes. Here is the difference. I am using a short cut by looking at the way waves travel and superimpose. My assumption is that the input impedance matches the impedance of the line. Thus 1v generates a 1v sine wave. For a simple example, such as any multiple of 1/2 wave, this causes current proportional to applied voltage and impedance of the line. For example, 50v applied to a 50 ohm line gives a 1 amp current. We know a line 1/2 wavelength long will absorb energy for the length of time it takes for a wave to travel the length of line and return, so power must be applied during the entire time. Obviously, 2 half waves will be applied over that time period so the amount of energy on the line is equal to the amount of energy contained in the power applied over time by two half waves, so total power applied is 2 * initial power. Equally obvious, by leaving the source connected after the reflected wave has returned, the question of how the source reacts to the external application of power must be answered. This is a second question, unrelated to traveling waves on a transmission line. My answer to this question is to disconnect the source and replace the source with a connection identical to the condition at the far end of the transmission line. You can see that this leaves the transmission line isolated with power circulating on the line (is is POWER, time is involved). Your solution (as presented in Analysis 2) and the Power Analysis was to keep the source supplied at all times in an attempt to create continuous real world conditions, as contrasted to my method of a quick and correctly timed disconnect. Both experiments are real world simulations and can be performed. Your analysis is identical to what happens at a real world transmitter. A very good, automatically tuned transmitter! Your choice of an ideal voltage source amounts to setting conditions that automatically adjust for impedance changes as fast as the change happens. The transmission line sees an outgoing impedance change going from 150 ohms to infinity in your example. The source sees an outgoing impedance change from 200 ohms to infinity during the same analysis period. It is interesting to compare the final voltage ratios ( directly proportional to energy levels and directly proportional to power levels) on the transmission line to the SWR ratio. You used a SWR ratio of 3:1 and I used 1:1. You found that the total energy stored on the line was 4 times the initial energy applied, and I predicted that the total energy stored was 2 times the initial. The link here is that the power storage factor(SF) (I know you dislike the term) is found from SF = SWR + 1. Your storage factor was SF = 3 + 1 = 4. My storage factor was SF = 1 + 1 = 2. If we can accept that the storage factor is always SF = SWR + 1 for all situations, then we have a very convient way to predict the voltage increase that results form impedance mismatch at a discontinuity. I am not yet ready to accept this generalization, but we should look at it more carefully. Ending comment. Both your and my analysis are correct. Congratulations to both us! 73, Roger, W7WKB |
Standing-Wave Current vs Traveling-Wave Current
Roger wrote:
If we can accept that the storage factor is always SF = SWR + 1 for all situations, then we have a very convient way to predict the voltage increase that results form impedance mismatch at a discontinuity. The s-parameter equations do that automatically. That's part of their usefulness. Incidentally, the power reflection coefficients, rho^2, and the power transmission coefficient, (1-rho^2), also do the same thing. That's why a power analysis is often easier than a voltage analysis. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Roger wrote:
Roy Lewallen wrote: Can you use your theory to show the voltage at all times at the input or, if you choose, just inside the input of the line, as I've done using conventional theory? Yes. Here is the difference. I am using a short cut by looking at the way waves travel and superimpose. My assumption is that the input impedance matches the impedance of the line. That's a different analysis than I did. I did two, one in which the mismatch was infinite (perfect voltage source at the input) and one in which the voltage reflection coefficient at the source was 0.5. The case where the input is matched is simpler, because there is no re-reflection from the source. Can your method be used to analyze a circuit which is mismatched at the source? Thus 1v generates a 1v sine wave. Sorry, I don't understand that sentence. For a simple example, such as any multiple of 1/2 wave, this causes current proportional to applied voltage and impedance of the line. For example, 50v applied to a 50 ohm line gives a 1 amp current. It does for the time for one round trip. Then the current drops to zero if the line is matched at the source. We know a line 1/2 wavelength long will absorb energy for the length of time it takes for a wave to travel the length of line and return, so power must be applied during the entire time. Yes. Obviously, 2 half waves will be applied over that time period so the amount of energy on the line is equal to the amount of energy contained in the power applied over time by two half waves, so total power applied is 2 * initial power. You've lost me here. What's "total power"? Can you express it as an equation? Equally obvious, by leaving the source connected after the reflected wave has returned, the question of how the source reacts to the external application of power must be answered. Well, the bit about "total power" wasn't obvious, so I'm not surprised that what follows isn't either. You're apparently assuming that there are waves of traveling power, which has led to demonstrably self-contradictory results before, but let's see where it leads this time. This is a second question, unrelated to traveling waves on a transmission line. My answer to this question is to disconnect the source and replace the source with a connection identical to the condition at the far end of the transmission line. Which I presume is the open circuited example. You can see that this leaves the transmission line isolated with power circulating on the line (is is POWER, time is involved). The power at any point can easily be calculated, and it shows that energy is moving back and forth on the line. There are no waves of power moving about. Your solution (as presented in Analysis 2) and the Power Analysis was to keep the source supplied at all times in an attempt to create continuous real world conditions, as contrasted to my method of a quick and correctly timed disconnect. Both experiments are real world simulations and can be performed. Ok. My method correctly predicts what will happen at any instant in either case. Let's see how yours does. Your analysis is identical to what happens at a real world transmitter. A very good, automatically tuned transmitter! I won't attempt to argue that, because of the great deal of controversy about what the characteristics of a "real world transmitter" are. I make no representation for my analysis other than what I stated: it uses an ideal voltage source, which is rigorously defined and with characteristics which are completely known, in conjunction with a perfect resistance. Your choice of an ideal voltage source amounts to setting conditions that automatically adjust for impedance changes as fast as the change happens. No, there is no change in impedance. The perfect source has a zero impedance at all times. The resistance has an impedance equal to its resistance at all times. The voltage of the voltage source stays constant (that is, it puts out a sine wave of constant amplitude and phase) at all times. The transmission line sees an outgoing impedance change going from 150 ohms to infinity in your example. No, it sees a constant 150 ohms at all times. The source sees an outgoing impedance change from 200 ohms to infinity during the same analysis period. If you consider the analysis period to extend to steady state, then yes, that's correct. You might recall that the power into the line increased for one of the reflection periods because of the improved impedance match between the source and line (impedances of 150 and 250 ohms respectively) compared to the impedance match at other periods. It is interesting to compare the final voltage ratios ( directly proportional to energy levels and directly proportional to power levels) on the transmission line to the SWR ratio. The energy stored = 1/2 * C * v^2 + 1/2 * L * i^2, where v and i are the voltage and current at a very short section of line, and C and L are the capacitance and inductance, respectively, per that short section. As you can see, energy is not directly proportional to V by any means. There are places and times where energy is stored entirely in the magnetic field, and v is zero. You used a SWR ratio of 3:1 and I used 1:1. No, the SWR on the line was infinite in my example. It's determined entirely by the load impedance and the line's Z0. If you're assuming an open ended line, the SWR is infinite in your example also. You found that the total energy stored on the line was 4 times the initial energy applied, No, the "initial energy" applied was zero. The analysis began with the assumption that the line was initially completely discharged. It sounds like you're confusing power, which had an initial value, and the energy, which accumulated over time. and I predicted that the total energy stored was 2 times the initial. Where and when did you predict that? What initial energy did you apply to the line? Can you do an analysis with the line initially discharged as I did? The link here is that the power storage factor(SF) (I know you dislike the term) is found from SF = SWR + 1. Your storage factor was SF = 3 + 1 = 4. My storage factor was SF = 1 + 1 = 2. First of all, the SWR in my example was infinite, so by your calculation, the "power storage factor" was infinite. If we can accept that the storage factor is always SF = SWR + 1 for all situations, then we have a very convient way to predict the voltage increase that results form impedance mismatch at a discontinuity. I am not yet ready to accept this generalization, but we should look at it more carefully. I still don't know what you mean by "power storage factor" or why you need to coin a new and vague term. So I guess I can accept that it's whatever you want it to be. But it has no relationship to power or energy that I can see. Ending comment. Both your and my analysis are correct. Congratulations to both us! I've presented an analysis which gives, quantitatively, the exact voltage at any point on the line, at any instant, from turn-on until steady state. I've also shown the power being applied at any instant and the total energy on the line at any time. You've presented an analysis whose only result is a poorly defined "power storage factor", derived from invalid premises. Yes, congratulations to us both. By the way, I didn't see from your "analysis" how many watts are stored in the line. If power is stored as you say, you surely must be able to determine how much. Roy Lewallen, W7EL |
Standing-Wave Current vs Traveling-Wave Current
Cecil Moore wrote:
Gene Fuller wrote: * Did you perhaps notice that the surfer typically travels much faster than the water? Surfers even travel faster than the wave energy. Sailboats travel faster than the wind. Unfortunately, for your argument, nothing in the universe (AFAWK) travels faster than an EM wave. But maybe you can invent Warp Drive or Slip-Stream Drive. :-) Huh??? What argument of mine requires superluminal velocities? Did I post something while I was sleeping? I hate it when I do that. 8-) 73, Gene W4SZ |
Standing-Wave Current vs Traveling-Wave Current
On 4 Jan, 10:31, "Dave" wrote:
art spewed: snip A radiator in equilibrium is a full wave length long ago, and far away... well maybe a couple months, and still in this group, you said 1/2 wave was the equilibrium size? *so which is it, full wave or half wave? *and where did gauss go?? *how do these funny cosmic dust things fit into his equation?? David you are quite correct in that I do fluctuate between a full wave length and a half wave length antenna which is obviously wrong. My problem in describing a wave length is to consider it in electric terms thus a physical halfwave radiator is electrically a full wave antenna since it handles one period. Ofcourse I should use standard terminology and refer to physical length even tho it is not exactly correct to my mind because it actually varies in the real world where as electrical length doesn't. However, I should stay with the accepted terminology to the best of my ability even tho I believe that is why this arguement on colliding current is realising postings and mass confusion in excess of 1000 each time it comes up. I apologise for misleading terminolgy. With reference to Gauss. This is my starting point where with the addition of a time variable to the static law became the same as Maxwells laws where Gauss formula was firmly in theIsaac Newton camp by revolving around gravitational fields. funny cosmic dust come into the equation Cosmic or galactic dust is everywhere on this earth .m. This dust is what Gauss refers to as static particles in a gravitational field in equilibrium. Thus I was able to add elements to this field as long as the elements were in equilibrium, together with a time vaying addition which brings it into Maxwells court. This transition to a dynamic form then allows the use of computor programs based only around Maxwells laws. Thus radiators and arrays could be designed based on a equilibrium format instead of a planar format as with a Yagi using existing standard computor radiator design programs. From the results the following becomes correct i.e A radiator can be any shape, size or elevation as long it is in aquilibrium and made from a diamagnetic material. Thus now helix radiators would have to have counter windings to fall with in these parameters, where the present helical antennas are absent the contra wound windings. All this is what Prof Hattely was looking for in combining the EH field which is unsuccesfull as is the latest RI antenna. None of these inventors followed the same trail that I did that revealed the equilibrium requirement for contra wound coil additions. Ask any other questions that you have difficulty with. As an aside, this was what Einstein was looking for during his last twenty years of life under the title of a Grand Unification theory but without success Regards Art Unwin....KB9MZ |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote:
On Jan 3, 12:55pm, Mike Monett wrote: [...] Your explanation is easily proven false. Let's suppose it was true. Suppose it was possible to introduce a pulse of charge onto a conductor. Since like charges repel each other, what keeps the pulse together? In other words, what prevents it from destroying itself? Then, when the first pulse meets the second, what mechanism allows them to bounce off each other? Then, after they have bounced off each other, what mechanism keeps them together? All good questions. For which you have no answers. But there's more bad news. Here's your original post of Dec 29: ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ Subject: Standing-Wave Current vs Traveling-Wave Current Date: Sat, 29 Dec 2007 14:33:46 -0800 (PST) From: Keith Dysart Newsgroups: rec.radio.amateur.antenna Keith Dysart wrote: [...] Consider a 50 ohm transmission line that is 4 seconds long with a pulse generator at one end and a 50 ohm resistor at the other. The pulse generator generates a single 1 second pulse of 50 volts into the line. Before and after the pulse its output voltage is 0. While generating the pulse, 1 amp (1 coulomb/s) is being put into the line, so the generator is providing 50 watts to the line. After one second the pulse is completely in the line. The pulse is one second long, contains 1 coulomb of charge and 50 joules of energy. It is 50 volts with 1 amp: 50 watts. Let's examine the midpoint (2 second) on the line. At two seconds the leading edge of the pulse arrives at the midpoint. The voltage rises to 50 volts and the current becomes 1 amp. One second later, the voltage drops back to 0, as does the current. The charge and the energy have completely passed the midpoint. When the pulse reaches the end of the line, 50 joules are dissipated in the terminating resistor. Notice a key point about this description. It is completely in terms of charge. There is not a single mention of EM waves, travelling or otherwise. Now we expand the experiment by placing a pulse generator at each end of the line and triggering them to each generate a 50V one second pulse at the same time. So after one second a pulse has completely entered each end of the line and these pulse are racing towards each other at the speed of light (in the line). In another second these pulses will collide at the middle of the line. What will happen? Recall one of the basics about charge: like charge repel. So it is no surprise that these two pulses of charge bounce off each and head back from where they came. At the center of the line, for one second the voltage is 100 V (50 V from each pulse), while the current is always zero. No charge crossed the mid-point. No energy crossed the mid-point (how could it if the current is always zero (i.e. no charge moves) at the mid-point. [...] So do the travelling waves "reflect" off each other? Save the term "reflect" for those cases where there is an impedance discontinuity and use "bounce" for those cases where no energy is crossing a point and even Cecil may be happy. But bounce it does. Keith ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ In order for the pulses to bounce off each other, your theory requires that electrons move at nearly the speed of light. Unfortunately, they do not. The classical formula for the drift velocity of electrons in a conductor is: v = I / (n * a * q) where v is the drift velocity of the electrons I is the current in Amperes n is the number of electrons per cubic metre, copper = 8.5e28 / m^3 A is the cross sectional area of the wire Q is the charge of an electron, 1.6e-19C References: http://amasci.com/miscon/speed.html http://physicsplus.blogspot.com/2007...electrons.html http://resources.schoolscience.co.uk...elech2pg3.html http://hyperphysics.phy-astr.gsu.edu...ic/ohmmic.html Using the 1 Amp from your post, if the center conductor has an area of 0.5 mm^2 (0.5e-6 m^2), the drift velocity is: v = 1 / (8.5e28 * 0.5e-6 * 1.6e-19) = 0.0001470 meters per second So in one second, the electrons move 0.147 mm. If the propagation constant of your line is 66%, the signal will propagate at: Vel = 3e8 * 0.66 = ~200e6 meters/sec If the pulses meet in the center of the line, that point is about 400 million meters away from the electrons that originally carried your pulse of charge. This raises many questions. How can the pulses bounce off each other if the electrons that carried the charge are 400 million meters away? Obviously, they can't. There's more bad news. If two collections of 1 Coulomb each were concentrated one meter apart, the force between them could be calculated from Coulomb's Law. In this example, the force is 1.01 million tons: http://hyperphysics.phy-astr.gsu.edu...ic/elefor.html This means the pulses could not even come close enough to bounce off each other. This would certainly wreck any timing analysis you try to do on the signals. So your theory fails simple logic tests, it requires invalid electron velocities, and it fails Coulomb's law. It is clear the pulses cannot bounce off each other, as you claim above when you state "But bounce it does." ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ But it appears that your underlying suggestion is that charge and charge flow in the distributed capacitance and inductance can not be used to analyze transmission lines. That is not what you proposed. Your post states: Notice a key point about this description. It is completely in terms of charge. There is not a single mention of EM waves, travelling or otherwise. ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ And yet I commonly see discussion of current in transmission lines. Current is charge flow per unit time. Is this all invalid? Must we abondon measurements of current? Voltage? These are all based on the assumption of charge being a useful concept. You are just trying to fog the issue. You cannot use charge by itself as you claim above. Keith Regards, Mike Monett |
Standing-Wave Current vs Traveling-Wave Current
On Jan 5, 1:07*am, mike wrote:
* Keith Dysart wrote: * On Jan 3, 12:55pm, Mike Monett wrote: * [...] * Your explanation *is *easily proven false. Let's *suppose *it was * true. * Suppose it *was *possible to introduce a pulse of *charge *onto a * conductor. * Since like *charges *repel *each * other, *what *keeps *the pulse * together? In *other *words, * what *prevents *it *from destroying * itself? * Then, when *the *first *pulse meets *the *second, *what mechanism * allows them to bounce off each other? * Then, after *they *have bounced off *each *other, *what mechanism * keeps them together? * All good questions. * For which you have no answers. * But there's more bad news. Here's your original post of Dec 29: * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * Subject: Standing-Wave Current vs Traveling-Wave Current * Date: Sat, 29 Dec 2007 14:33:46 -0800 (PST) * From: Keith Dysart * Newsgroups: rec.radio.amateur.antenna * Keith Dysart wrote: * [...] * Consider a 50 ohm transmission line that is 4 seconds long *with a * pulse generator at one end and a 50 ohm resistor at the other. * The pulse generator generates a single 1 second pulse of *50 volts * into the line. Before and after the pulse its output voltage is 0. * While generating the pulse, 1 amp (1 coulomb/s) is being *put into * the line, so the generator is providing 50 watts to the line. * After one second the pulse is completely in the line. * The pulse is one second long, contains 1 coulomb of charge *and 50 * joules of energy. It is 50 volts with 1 amp: 50 watts. * Let's examine the midpoint (2 second) on the line. * At two *seconds *the *leading edge of *the *pulse *arrives *at the * midpoint. The voltage rises to 50 volts and the current *becomes 1 * amp. One *second later, the voltage drops back to 0, *as *does the * current. The *charge *and the energy *have *completely *passed the * midpoint. * When the *pulse *reaches *the *end *of *the *line, *50 *joules are * dissipated in the terminating resistor. * Notice a *key *point about this description. It *is *completely in * terms of *charge. *There *is not a *single *mention *of *EM waves, * travelling or otherwise. * Now we expand the experiment by placing a pulse generator *at each * end of *the *line and triggering them to each generate *a *50V one * second pulse *at *the same time. So after one second *a *pulse has * completely entered each end of the line and these pulse are racing * towards each other at the speed of light (in the line). In another * second these pulses will collide at the middle of the line. * What will *happen? *Recall one of the *basics *about *charge: like * charge repel. So it is no surprise that these two pulses of charge * bounce off each and head back from where they came. At *the center * of the *line, for one second the voltage is 100 V (50 V *from each * pulse), while *the current is always zero. No *charge *crossed the * mid-point. No *energy crossed the mid-point (how could *it *if the * current is always zero (i.e. no charge moves) at the mid-point. * [...] * So do the travelling waves "reflect" off each other? Save the term * "reflect" *for * those * cases * where * there * is * an impedance * discontinuity and use "bounce" for those cases where no *energy is * crossing a point and even Cecil may be happy. But bounce it does. * Keith * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * In order *for *the *pulses to bounce *off *each *other, *your theory * requires that electrons move at nearly the speed of light. It might best be called a hypothesis, but I don't think it requires that electrons move at the speed of light, rather charge move at the speed of light. This would seem consistent with normal explanations where charge starts to enter the line at some time T and starts to exit the line at T + distance/speedOfLight later. [snipped, an interesting computation of the speed of electros] * There's more *bad *news. If two collections of 1 *Coulomb *each were * concentrated one *meter *apart, *the *force *between *them *could be * calculated from *Coulomb's Law. In this example, the *force *is 1.01 * million tons: * *http://hyperphysics.phy-astr.gsu.edu...ic/elefor.html * This means the pulses could not even come close enough to bounce off * each other. *This would certainly wreck any timing analysis *you try * to do on the signals. Another interesting analysis. It raises the question of how a pulse containing one coulomb over a measurable length of line actually maintains its shape and does not immediately disperse. This is a detail well beyond my knowledge, but I could speculate that it is related to the inductance and forces of the resulting magnetic field. I'd further speculate that the force between the pulses can not travel faster than the speed of light, and since the pulse itself is travelling at the speed of light, the two pulses reach each other at the same time that force does. * So your *theory *fails *simple * logic *tests, *it *requires invalid * electron velocities, and it fails Coulomb's law. * It is *clear the pulses cannot bounce off each other, *as *you claim * above when you state "But bounce it does." * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * But it appears that your underlying suggestion is that *charge and * charge flow in the distributed capacitance and inductance *can not * be used to analyze transmission lines. * That is not what you proposed. Your post states: Perhaps I was not clear in my post. In any case, the question is fundamental... Can charge and charge flow in the distributed capacitance and inductance be used to analyze transmission lines? * Notice a *key *point about this description. It *is *completely in * terms of *charge. *There *is not a *single *mention *of *EM waves, * travelling or otherwise. * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * And yet *I *commonly *see discussion *of *current *in transmission * lines. Current is charge flow per unit time. Is this all invalid? * Must we *abondon measurements of current? Voltage? *These *are all * based on the assumption of charge being a useful concept. * You are *just *trying *to fog the issue. You *cannot *use *charge by * itself as you claim above. No. I am just trying to make clear the consequences of choosing "no" as the answer to the question I directly posed above. ...Keith |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote:
It might best be called a hypothesis, but I don't think it requires that electrons move at the speed of light, rather charge move at the speed of light. Anything moving at the speed of light in a transmission line is photonic in nature. The nature of photons is well known and they do not repel each other. They have electric and magnetic fields but no charge. So there's no charge moving at the speed of light in a transmission line. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
"Keith Dysart" wrote in message ... On Jan 5, 1:07 am, mike wrote: Keith Dysart wrote: Can charge and charge flow in the distributed capacitance and inductance be used to analyze transmission lines? yes. that is the classical derivation shown in any decent text book. You are just trying to fog the issue. You cannot use charge by itself as you claim above. No. I am just trying to make clear the consequences of choosing "no" as the answer to the question I directly posed above. moving charge is current. current traveling waves are well defined and analyzed by existing methods. as stated before and well documented in existing texts you need only analyze the current OR the voltage traveling waves in a transmission line to get the full picture since one is always linearly related to the other by Z0. waves traveling in opposite directions do not interact, they don't 'bounce' off of each other, they just pass right through each other as long as the conditions required for superposition apply, which is almost all the time in amateur installations. |
Standing-Wave Current vs Traveling-Wave Current
Cecil, W5DXP wrote:
"Unfortunately for your argument, nothing in the universe (AFAWK) travels faster than an EM wave. But maybe you can invent Warp Drive or Slip-Stream Drive. :-)" Nothing to do with the argument, but I believe there is an exception that comes to exceeding the speed of light, and that is when the wave is slowed in a medium to a speed less than c. |
Standing-Wave Current vs Traveling-Wave Current
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Standing-Wave Current vs Traveling-Wave Current
On 5 Jan, 05:38, Keith Dysart wrote:
On Jan 5, 1:07*am, mike wrote: * Keith Dysart wrote: * On Jan 3, 12:55pm, Mike Monett wrote: * [...] * Your explanation *is *easily proven false. Let's *suppose *it was * true. * Suppose it *was *possible to introduce a pulse of *charge *onto a * conductor. * Since like *charges *repel *each * other, *what *keeps *the pulse * together? In *other *words, * what *prevents *it *from destroying * itself? * Then, when *the *first *pulse meets *the *second, *what mechanism * allows them to bounce off each other? * Then, after *they *have bounced off *each *other, *what mechanism * keeps them together? * All good questions. * For which you have no answers. * But there's more bad news. Here's your original post of Dec 29: * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * Subject: Standing-Wave Current vs Traveling-Wave Current * Date: Sat, 29 Dec 2007 14:33:46 -0800 (PST) * From: Keith Dysart * Newsgroups: rec.radio.amateur.antenna * Keith Dysart wrote: * [...] * Consider a 50 ohm transmission line that is 4 seconds long *with a * pulse generator at one end and a 50 ohm resistor at the other. * The pulse generator generates a single 1 second pulse of *50 volts * into the line. Before and after the pulse its output voltage is 0. * While generating the pulse, 1 amp (1 coulomb/s) is being *put into * the line, so the generator is providing 50 watts to the line. * After one second the pulse is completely in the line. * The pulse is one second long, contains 1 coulomb of charge *and 50 * joules of energy. It is 50 volts with 1 amp: 50 watts. * Let's examine the midpoint (2 second) on the line. * At two *seconds *the *leading edge of *the *pulse *arrives *at the * midpoint. The voltage rises to 50 volts and the current *becomes 1 * amp. One *second later, the voltage drops back to 0, *as *does the * current. The *charge *and the energy *have *completely *passed the * midpoint. * When the *pulse *reaches *the *end *of *the *line, *50 *joules are * dissipated in the terminating resistor. * Notice a *key *point about this description. It *is *completely in * terms of *charge. *There *is not a *single *mention *of *EM waves, * travelling or otherwise. * Now we expand the experiment by placing a pulse generator *at each * end of *the *line and triggering them to each generate *a *50V one * second pulse *at *the same time. So after one second *a *pulse has * completely entered each end of the line and these pulse are racing * towards each other at the speed of light (in the line). In another * second these pulses will collide at the middle of the line. * What will *happen? *Recall one of the *basics *about *charge: like * charge repel. So it is no surprise that these two pulses of charge * bounce off each and head back from where they came. At *the center * of the *line, for one second the voltage is 100 V (50 V *from each * pulse), while *the current is always zero. No *charge *crossed the * mid-point. No *energy crossed the mid-point (how could *it *if the * current is always zero (i.e. no charge moves) at the mid-point. * [...] * So do the travelling waves "reflect" off each other? Save the term * "reflect" *for * those * cases * where * there * is * an impedance * discontinuity and use "bounce" for those cases where no *energy is * crossing a point and even Cecil may be happy. But bounce it does. * Keith * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * In order *for *the *pulses to bounce *off *each *other, *your theory * requires that electrons move at nearly the speed of light. It might best be called a hypothesis, but I don't think it requires that electrons move at the speed of light, rather charge move at the speed of light. This would seem consistent with normal explanations where charge starts to enter the line at some time T and starts to exit the line at T + distance/speedOfLight later. [snipped, an interesting computation of the speed of electros] * There's more *bad *news. If two collections of 1 *Coulomb *each were * concentrated one *meter *apart, *the *force *between *them *could be * calculated from *Coulomb's Law. In this example, the *force *is 1.01 * million tons: * *http://hyperphysics.phy-astr.gsu.edu...ic/elefor.html * This means the pulses could not even come close enough to bounce off * each other. *This would certainly wreck any timing analysis *you try * to do on the signals. Another interesting analysis. It raises the question of how a pulse containing one coulomb over a measurable length of line actually maintains its shape and does not immediately disperse. This is a detail well beyond my knowledge, but I could speculate that it is related to the inductance and forces of the resulting magnetic field. I'd further speculate that the force between the pulses can not travel faster than the speed of light, and since the pulse itself is travelling at the speed of light, the two pulses reach each other at the same time that force does. * So your *theory *fails *simple * logic *tests, *it *requires invalid * electron velocities, and it fails Coulomb's law. * It is *clear the pulses cannot bounce off each other, *as *you claim * above when you state "But bounce it does." * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * But it appears that your underlying suggestion is that *charge and * charge flow in the distributed capacitance and inductance *can not * be used to analyze transmission lines. * That is not what you proposed. Your post states: Perhaps I was not clear in my post. In any case, the question is fundamental... Can charge and charge flow in the distributed capacitance and inductance be used to analyze transmission lines? * Notice a *key *point about this description. It *is *completely in * terms of *charge. *There *is not a *single *mention *of *EM waves, * travelling or otherwise. * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ ~~~~~~~~~~~~~~~~~~ * And yet *I *commonly *see discussion *of *current *in transmission * lines. Current is charge flow per unit time. Is this all invalid? * Must we *abondon measurements of current? Voltage? *These *are all * based on the assumption of charge being a useful concept. * You are *just *trying *to fog the issue. You *cannot *use *charge by * itself as you claim above. No. I am just trying to make clear the consequences of choosing "no" as the answer to the question I directly posed above. ...Keith- Hide quoted text - - Show quoted text - Keith, if you could get people to subscribe to hyperphysics so that they may read of the tremendous strides with respect to radiation,it's speed, acute angles of radiation and the relationships to light and even to the solar system, especially with respect to the Milky way. All of these discussions with respect to collision of waves would disappear, since all laws are based around equilibrium. When equilibrium is broken as with a radiator that is not resonant one cannot procede as normal in translating existing laws for a unbalanced situation. When one does this one enters a circular debate that has no end like this one which many suposedly experts have deviated from cardinal laws. If these so called "experts" kept up with the modern phases of science as shown by hyperphysics which you have pointed to instead of remaining inthe stable position of their junior years learning by rote they would be constantly reminded of the importance of confining them selves to the world of equilibrium. Alas, they prefer to live in the confines of the past where modern physisists prefer to keep pace with knoweledge. However, these new physists only communicate between themselves such there is a barrier between the old and the new, those who seek knoweledge and those that are content with the world of the past. Regards Art |
Standing-Wave Current vs Traveling-Wave Current
Richard Harrison wrote:
Cecil, W5DXP wrote: "Unfortunately for your argument, nothing in the universe (AFAWK) travels faster than an EM wave. But maybe you can invent Warp Drive or Slip-Stream Drive. :-)" Nothing to do with the argument, but I believe there is an exception that comes to exceeding the speed of light, and that is when the wave is slowed in a medium to a speed less than c. Sometimes EM waves travel at less than the speed of light in a vacuum but they are still traveling at the speed of light in the medium. VF*c is still the speed of light. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
On 4 Jan, 09:17, art wrote:
On 3 Jan, 08:29, John Smith wrote: Mike Monett wrote: ... * The term *"bounce" means they interact. *Electromagnetic *signals do * not interact. *They *superimpose. *Each *is *completely *unaware and * unaffected by the other. ... * Regards, * Mike Monett EM fields act that same as static magnetic fields. Why not just get some iron filings, a paper and a couple of magnets? Move the magnets about below the paper with the iron filings above and actually get a visual on some magnetic fields and how they react to each other? I like things simple ... then the math can follow ... Regards, JS John You are quite correct in requiring things to be relatively *simple . And RF is very simple when you do not try to make it difficult. A radiator in equilibrium is a ELECTRICAL full wave length ( a half wave PHYSICAL length radiator) *and equates *a mechanical pendulum which is about as close as you can get to perpetual motion Electrically it is seen as a parallel circuit sometimes called a tank circuit. It to like a pendulum passes the same energy backwards and forward and losing just a bit to resistance losses.Ofcourse everybody knows that the pendulum has also a circular motion as well as backwards and forwards so if RF is to be compared to a pendulum we must be sure to account for that rotative motion. Nothing so far is anything unusual. Now we supply energy to the circuit or radiator. The initial current enters the inductance and generates a magnetic field. The current applied then reverses because it is AC or periodic DC. Without support from flowing current the magnetic field starts to collaps such that the energy that it generates moves on the the capacitor which like the inductor will stop the enrgy from getting by and thus stores it, It acts in a mirror image or opposite fashion to that of a conductor, when one discharges the other collects what is discharged. So far John it is all very simple since this can go on for ever backwards and forwards and if we lose a bit of energy along the way the current generator is there to replace what is lost. Now we must look at the radiation properties as well as that circular movement that we saw with the pendulum which is the only thing left to describe. In the atmosphere we have lots of dust that has penetrated the shields around earth. These are nothing fancy just dust particles. Actually these particles are called static particles and they just want to rest somewhere.The odd thing here that all metals will not allow it to settle on them because like magnets with a hysterysis content they push away this galactic dust. Fortunately there are some metals and matter that do not retain a internal hysterysis energy pack like aluminum and copper and water so this duct pretty much seeks these out to settle on. Nothing really difficults so far John, no fancy names or fancy bouncing. So you see the reason why aluminum is used for radiators because they belong to a familly known as diamagnetic material. So what is so fancy about using aluminum to transport energy backwards and forward since aluminum is not specifically used for pendulums? well there is a specific reasons that the properties of aluminium fits in with current flow and RF generation. First it has a skin that is difficult for current to penetrate so any field produced by current can only be created outside the skin which unlike magnet material the field cannot penetrate the inner material. Fortunately it is conductive, on the othere side of the coin the field generated are weak because they do not have internal magnetic fields in the metal to support them. Still nothing special John , just a circuit sort of thing, no proton things or fancy names to muddy up the water. Noe let us look again as to what happens in the circuit. Yup when the inductance creates a magnetic field it is a very weak field so the energy passed on to the cappacitor is very small. Never the less the acction of back and forth still goes on. Now is when all the special things happen. ............................................. The capacitor releases its energy like a blast of a opening door where the electrons stored with energy in their pockets blast their way towards the inductance. On the way it sweeps up its brethberin electron particles that are devoid of energy on its way to the inductor. The inductor is not interested in static or energy less electrons since the static does not have any usefull energy required to make a mabnetic field .So the magnetic field is generated on the outside of the inductance but here is the guts of radiation. Diagmatic materials when they produce a field produces a field at right angles to a normal ferromagnetic field. This field tho very weak parries the oncomming static particles away. The action spoken of for a momement disturbs the equilibrium that was in place such that the airborne static particles are thrown away from the earth's gravitational field. Pretty neat John, nothing really new since all characteristics and properties are well known and documented. Now reviewing what happenned and comparing it to a pendulum. Yup we had a back and forth motion but we already knew that because it was a tank circuit. The weak movement of the magnetic field created a 'curling' type action which paried the onrushing levitated particles away from the immediate scene. WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL At the same time when all these levitated particals was forced upwards away from the radiator each particle provided an equal and opposite force which is applied to the radiator *the impacts of which reflecting the changing energy flow from the capacitor. These multi impacts create a mechanical oscillation within the radiator. See John, again nothing special, everything is known. It is just that like a jigsaw puzzle the complexity of which is determined from where one starts which in my case started with the Gaussian theory.The experts on the other hand did not know where to start so they inaiated new sciences *Oh, and another thing those particles that are now trying to escape the earth's gravity field and in some cases bouncing off of the earths layers and comming back looking for a radiater of the right material that it can arrive at to settle upon thus making a series of noises like a muscical box with a fantastic caphony of sound andc vivrations on a resonal antenna.( A MHZ IS A MILLION CYCLES SO ONE CAN IMAGINE THE NUMBER OF IMPACT SAMMLES ARE TRANSFERED WHEN AUDIO OCCURRES) As I said before John,no fancy names or extra things moving around to take you attention away from what is really happening. All concurring phenomina is a matter of record by past very clever people which is beyond any doubt and, and I say 'and' like nature the mechanics of action are very, very simple. Ofcourse the big this that all the above is corroberated using existing antenna computor programs on antennas when an optimiser is used or you can google the steps taken at every instance Best Regards Art Unwin.....KB9MZ...XG (uk)- Hide quoted text - - Show quoted text - |
Standing-Wave Current vs Traveling-Wave Current
art blathered on and scribbled:
WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL so, you should be able to take a compass, a piece of copper wire, and a piece of steel or iron wire and tell the difference between the material just by passing a dc current through them? |
Standing-Wave Current vs Traveling-Wave Current
On 6 Jan, 09:40, "Dave" wrote:
art blathered on and scribbled: WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL so, you should be able to take a compass, a piece of copper wire, and a piece of steel or iron wire and tell the difference between the material just by passing a dc current through them? David It certainly is not the same axis as the material that the current is travelling through! Remember my comments with respect to a pendulum when a eclipse occures, and the happennings in the Bermuda triangle! If you did go to college look up your 101 notes or review the new thread I have started for amateurs and socalled experts. David, I am like an ever ready battery, I keep going and going until I can educate all about how radiation occurs in a scientific fashion to those who are not educated. Unless debate points out errors that can be substantiated I will go on and on and on and.... Art Unwin....KB9MZ....xg (uk) |
Standing-Wave Current vs Traveling-Wave Current
in his own world, art let loose with more words of wisdom: WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL so, you should be able to take a compass, a piece of copper wire, and a piece of steel or iron wire and tell the difference between the material just by passing a dc current through them? It certainly is not the same axis as the material that the current is travelling through! Remember my comments with respect to a pendulum when a eclipse occures, and the happennings in the Bermuda triangle! ok, lets make this simple. what is the equation for the vector representation of the magnetic field around an infinitely long straight wire made of copper? and what is the equation for it around a wire made of iron? and how do they relate to the bermuda triangle? show all work, and complete before the next eclipse. |
Standing-Wave Current vs Traveling-Wave Current
On Jan 6, 1:28 pm, art wrote:
David, I am like an ever ready battery, I keep going and going until I can educate all about how radiation occurs in a scientific fashion to those who are not educated. Unless debate points out errors that can be substantiated I will go on and on and on and.... Art Unwin....KB9MZ....xg (uk) "Educating" people using copious amounts of bafflegab has been proven by Underwriters Laboratory to be a hazard to carbon life forms of all types. You should cease and desist from this illogical behavior says Dr. Spock. Captain Kirk seems to be in full agreement. I asked Dr. McCoy about this, and he said, "Oh hell, it's too much of that Vulcan Ale he's been drinking". Scotty had no comment, but only scratched his head in disgust, and starting mumbling something about dilithium crystals never being in a true state of equilibrium, even under the strict care and supervision of Dr. McCoy. As a final comment, Captain Kirk said, well, there you have it then, bafflgab is never in a true state of equilibrium. Even on the Enterprise. MK |
Standing-Wave Current vs Traveling-Wave Current
Dave wrote:
in his own world, art let loose with more words of wisdom: WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL so, you should be able to take a compass, a piece of copper wire, and a piece of steel or iron wire and tell the difference between the material just by passing a dc current through them? It certainly is not the same axis as the material that the current is travelling through! Remember my comments with respect to a pendulum when a eclipse occures, and the happennings in the Bermuda triangle! ok, lets make this simple. what is the equation for the vector representation of the magnetic field around an infinitely long straight wire made of copper? and what is the equation for it around a wire made of iron? and how do they relate to the bermuda triangle? show all work, and complete before the next eclipse. There's no point in being a smart-ass, Chip. You don't have any better grasp of electromagnetic theory than anyone else on this newsgroup, including Art. 73, Tom Donaly, KA6RUH |
Standing-Wave Current vs Traveling-Wave Current
wrote in message ... On Jan 6, 1:28 pm, art wrote: David, I am like an ever ready battery, I keep going and going until I can educate all about how radiation occurs in a scientific fashion to those who are not educated. Unless debate points out errors that can be substantiated I will go on and on and on and.... Art Unwin....KB9MZ....xg (uk) "Educating" people using copious amounts of bafflegab has been proven by Underwriters Laboratory to be a hazard to carbon life forms of all types. You should cease and desist from this illogical behavior says Dr. Spock. Captain Kirk seems to be in full agreement. I asked Dr. McCoy about this, and he said, "Oh hell, it's too much of that Vulcan Ale he's been drinking". Scotty had no comment, but only scratched his head in disgust, and starting mumbling something about dilithium crystals never being in a true state of equilibrium, even under the strict care and supervision of Dr. McCoy. As a final comment, Captain Kirk said, well, there you have it then, bafflgab is never in a true state of equilibrium. Even on the Enterprise. MK live long and prosper. me thinks that art is a bit out of equilibrium... but its fun to try and tweak him into contradicting himself, which he does frequently. |
Standing-Wave Current vs Traveling-Wave Current
Dave wrote:
wrote in message ... On Jan 6, 1:28 pm, art wrote: David, I am like an ever ready battery, I keep going and going until I can educate all about how radiation occurs in a scientific fashion to those who are not educated. Unless debate points out errors that can be substantiated I will go on and on and on and.... Art Unwin....KB9MZ....xg (uk) "Educating" people using copious amounts of bafflegab has been proven by Underwriters Laboratory to be a hazard to carbon life forms of all types. You should cease and desist from this illogical behavior says Dr. Spock. Captain Kirk seems to be in full agreement. I asked Dr. McCoy about this, and he said, "Oh hell, it's too much of that Vulcan Ale he's been drinking". Scotty had no comment, but only scratched his head in disgust, and starting mumbling something about dilithium crystals never being in a true state of equilibrium, even under the strict care and supervision of Dr. McCoy. As a final comment, Captain Kirk said, well, there you have it then, bafflgab is never in a true state of equilibrium. Even on the Enterprise. MK live long and prosper. me thinks that art is a bit out of equilibrium... but its fun to try and tweak him into contradicting himself, which he does frequently. Which, of course, doesn't say anything about Art, but does speak volumes about you. 73, Tom Donaly, KA6RUH |
Standing-Wave Current vs Traveling-Wave Current
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Standing-Wave Current vs Traveling-Wave Current
On Jan 6, 2:29 pm, "Dave" wrote:
live long and prosper. me thinks that art is a bit out of equilibrium... but its fun to try and tweak him into contradicting himself, which he does frequently. He doesn't have to be tweaked. He seems to grab at every straw that is within reach. Oh, and it's not like I hang around just to tweak Art.. And I'm surely no expert at electromagnetic theory compared to many here. But on the other hand, I don't spew out bafflegab on a weekly basis either though, and then try to claim said "theory" as fact. And that I am an expert, and everyone else is surely brain dead if they don't except said bafflegab as gospel. Art does this though. This is why it's hard to resist tweaking him every once in a while. :/ He may well be on to some new exotic theory to set all mankind on it's tail, but if he can't describe it without using bafflegab, no one will ever be able to tell what he is talking about. Myself, I'm not holding my breath... I don't believe in free lunches. Dr. Spock was a famous human pediatrician. Although perhaps not an expert on logic, he did write volumes about how to deal with children. So his advice is entirely appropriate in this situation, probably even more so than from the Mr. Spock of Star Trek. Roy Lewallen, W7EL Humm, I was thinking Mr. Spock was a "doctor" too, but maybe he wasn't.. He might as well have been vs the rest of the crew... :/ MK |
Standing-Wave Current vs Traveling-Wave Current
Aet wrote:
"WHY? beCAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL. My experience with broadcast towers is that it matters not if a steel tower is painted or zinc coated it works the same. Terman`s 1955 opus says on page 21: "When a current is flowing through such a conductor (he makes no distinction between iron or copper, but does describe an isolated round wire), the magnetic flux that results is in the form of concentric circles, as shown in Fig. 2-9. It is to be noted that some of the flux exists within the conductor and therefore links with , i.e.,encircles, current near the center of the conductor while not linking with current flowing near the surface. The result is that the inductance of the central part of the conductor is greater than the inductance of the part of the conductor near the surface; this is because of the greater number of flux linkages existing in the central region." Terman is describing "skin effect". "Right hand rule" definitions also say magnetic flux encircles the current carrying conductor. Art`s assertion is "off the wall". Best regards, Richard Harrison, KB5WZI |
Standing-Wave Current vs Traveling-Wave Current
On 6 Jan, 12:29, "Dave" wrote:
wrote in message ... On Jan 6, 1:28 pm, art wrote: David, I am like an ever ready battery, I keep going and going until I can educate all about how radiation occurs in a scientific fashion to those who are not educated. Unless debate points out *errors that can be substantiated I will go on and on and on and.... Art Unwin....KB9MZ....xg (uk) "Educating" people using copious amounts of bafflegab has been proven by Underwriters Laboratory to be a hazard to carbon life forms of all types. You should cease and desist from this illogical behavior says Dr. Spock. Captain Kirk seems to be in full agreement. I asked Dr. McCoy about this, and he said, "Oh hell, it's too much of that Vulcan Ale he's been drinking". *Scotty had no comment, but only scratched his head in disgust, and starting mumbling something about dilithium crystals never being in a true state of equilibrium, even under the strict care and supervision of Dr. McCoy. As a final comment, Captain Kirk said, well, there you have it then, bafflgab is never in a true state of equilibrium. Even on the Enterprise. MK live long and prosper. me thinks that art is a bit out of equilibrium... but its fun to try and tweak him into contradicting himself, which he does frequently.- Hide quoted text - - Show quoted text - Probably so. But pseudo experts such as Roy and Tom and the three Richards can't put o neck hold on the advances of science for ever, for people like MK to follow in lockstep in the absence of knoweledge. As for you Dave you can never move forward while resisting the notion that the addition of a time varient field to Gaussian law of Statics becomes the same as Maxwell's law. Without understanding the relationships of laws with the state of equilibrium you will never exceed beyond the learning level of your professor, only their equal. Because of learning by rote without understanding of the first principles of science all of which revolve around the lynch pin of equilibrium. But you are not alone. All of the so called experts on this newsgroup are guilty of the same thing hanging on to the writings of Terman and other oldies while ignoring or resisting the movement of science during the last half century. But then today,s interests of hams is talking and handwaving and not the intricacies of modern science with respect to radiation. Art Unwin KB9MZ....XG (uk) |
Standing-Wave Current vs Traveling-Wave Current
Art wrote:
"Tom and the three Richards can`t put a neck hold on the advance of science forever." Permanent magnets are collections of current loops, so it is supposed thet the earth`s magnetism is caused by currents in the earth. Its poles approach alignment with the earth`s axis of rotation. Solar storms are seen to affect the earth`s magnetism and evidence exists that poles have reversed over the eons of history. The most recent reversal came about 2.5 million years ago. "College Physics" by Frank Miller, Jr. is the source of the above. Best regards, Richard Harrison, KB5WZI |
Standing-Wave Current vs Traveling-Wave Current
On 6 Jan, 14:14, (Richard Harrison) wrote:
Aet wrote: "WHY? beCAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL. My experience with broadcast towers is that it matters not if a steel tower is painted or zinc coated it works the same. Terman`s 1955 opus says on page 21: "When a current is flowing through such a conductor (he makes no distinction between iron or copper, but does describe an isolated round wire), the magnetic flux that results is in the form of concentric circles, as shown in Fig. 2-9. It is to be noted that some of the flux exists within the conductor and therefore links with , i.e.,encircles, current near the center of the conductor while not linking with current flowing near the surface. The result is that the inductance of the central part of the conductor is greater than the inductance of the part of the conductor near the surface; this is because of the greater number of flux linkages existing in the central region." Terman is describing "skin effect". "Right hand rule" definitions also say magnetic flux encircles the current carrying conductor. Art`s assertion is "off the wall". Best regards, Richard Harrison, KB5WZI * No. It is keeping up to date. Terman died before all these things become known and basically you are also dead when you cannot move forward with the times. Go to google and look up diamagnetic materials and diamagnetic fields. While you are at it check out the rotation of a pendulum and how its curls are explained. While you are at it explain why a radiator being parallel to the earth does not produce as much horizontal gain as a tipped antenna.I dare you to come back and explain what you discovered. You can't hold back father time or the advance of science by holding on to old books. Methinks you are better staying with ficticious waves that bounce into each other with the other instant experts. Art |
Standing-Wave Current vs Traveling-Wave Current
art wrote:
WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL Does it matter that aluminum and copper are paramagnetic rather than diamagnetic? Perhaps you should consider a bismuth antenna. That is the poster child for diamagnetic metals. 73, Gene W4SZ |
Standing-Wave Current vs Traveling-Wave Current
On 6 Jan, 17:10, Gene Fuller wrote:
art wrote: WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL Does it matter that aluminum and copper are paramagnetic rather than diamagnetic? Perhaps you should consider a bismuth antenna. That is the poster child for diamagnetic metals. 73, Gene W4SZ Yes, bismuth would be the ideal material. On the other hand my understanding is aluminum, copper,water, gold and the like are diamagnetic materials. I am basing that on the magnetic susceptability values and the like to make that distinction.Where are you drawing the line with respect to diamagnetic and paramagnetic? The idea of using a ingredient that could smother an already weak paramagnetic field seams to thwart the actions that I am refering to. Regards Art |
Standing-Wave Current vs Traveling-Wave Current
art wrote:
Probably so. But pseudo experts such as Roy and Tom and the three Richards can't put o neck hold on the advances of science for ever, for people like MK to follow in lockstep in the absence of knoweledge. Crikeys, Art! How on earth are your nemeses strangling science? Does anyone in here take these bar room brawls seriously? I mean just what would this strangulation achieve? Does IEEE keep an archive of rraa? the National Science Foundation? These arguments, For all their sound and fury, signify nothing. I rather thought that they boys were all just feeling their oats. At any rate, the great unwashed such as myself find it all amusing. - 73 de Mike N3LI - |
Standing-Wave Current vs Traveling-Wave Current
On 7 Jan, 10:15, Michael Coslo wrote:
art wrote: Probably so. But pseudo experts such as Roy and Tom and the three Richards can't put o neck hold on the advances of science for ever, for people like MK to follow in lockstep in the absence of knoweledge. * * * * Crikeys, Art! How on earth are your nemeses strangling science? Does anyone in here take these bar room brawls seriously? * * * * I mean just what would this strangulation achieve? Does IEEE keep an archive of rraa? the National Science Foundation? * * * * These arguments, For all their sound and fury, signify nothing. I rather thought that they boys were all just feeling their oats. At any rate, the great unwashed such as myself find it all amusing. * * * * - 73 de Mike N3LI - In the scientific world it is a closed community and only within that community can members create change. So you often hear that some very clever people did not have their ideas examined until after they were dead which can be a hundred years.Hams are a similar closed community with respect to what creates radiation since they only accept books and will not or cannot debate any alternatives.When in college you are encouraged to debate which is way to retreat to the beginings and build up a case in opposition to the opponent.This cannot happen in ham radio because debates cannot happen except by those that deem themselves as experts whose mission is to protect the status quo Thus to become an expert one must follow the written word and deride those that deign to question the status quo.When was the last to you read of an open debate that was thouroughly discussed to a acceptable conclusion? Well you haven't heard one because when two heads debate one will always use personal attack as a means of retaliation.And I mean always. There is one discussion on this newsgroup that has gone on for several years and thousands of postings about travelling waves which I for one consider them to be ficticious in a resonant system. Do you ever believe one side or the other will demonstrate the concepts so all are on a common stage.? Hell no! Personal attacks were started years ago in an attempt to cut down the debate and all must resign themselves that the instant experts will defend the status quo for ever. Will we ever see a painter sell his paintings for millions while he is still alive? Such is life! Such is death! Art |
Standing-Wave Current vs Traveling-Wave Current
art wrote:
On 7 Jan, 10:15, Michael Coslo wrote: art wrote: Probably so. But pseudo experts such as Roy and Tom and the three Richards can't put o neck hold on the advances of science for ever, for people like MK to follow in lockstep in the absence of knoweledge. Crikeys, Art! How on earth are your nemeses strangling science? Does anyone in here take these bar room brawls seriously? I mean just what would this strangulation achieve? Does IEEE keep an archive of rraa? the National Science Foundation? These arguments, For all their sound and fury, signify nothing. I rather thought that they boys were all just feeling their oats. At any rate, the great unwashed such as myself find it all amusing. - 73 de Mike N3LI - In the scientific world it is a closed community and only within that community can members create change. This sounds like an indictment of the whole peer reviewed process. It's kind of like saying that People who have driver's licenses are a closed group. So you often hear that some very clever people did not have their ideas examined until after they were dead which can be a hundred years. Any cites here? Hams are a similar closed community with respect to what creates radiation since they only accept books and will not or cannot debate any alternatives. Here we really disagree! There is an amazing amount of antenna hokum scattered about among amateurs. When in college you are encouraged to debate which is way to retreat to the beginings and build up a case in opposition to the opponent.This cannot happen in ham radio because debates cannot happen except by those that deem themselves as experts whose mission is to protect the status quo Thus to become an expert one must follow the written word and deride those that deign to question the status quo.When was the last to you read of an open debate that was thouroughly discussed to a acceptable conclusion? Well you haven't heard one because when two heads debate one will always use personal attack as a means of retaliation.And I mean always. Art, here is where you make a huge mistake. You are bringing personal "feelings" into the equation. Who really gives a whoop doop dingle about feelings? With your Mechanical engineering background, I assume that you must have sat in on design and other meetings. Many of the ones I have sat in have become plenty heated. So What? We leave the meeting and go get the job done. Then we enjoy a beer with the people we were arguing with after work. There is one discussion on this newsgroup that has gone on for several years and thousands of postings about travelling waves which I for one consider them to be ficticious in a resonant system. Do you ever believe one side or the other will demonstrate the concepts so all are on a common stage.? Hell no! Respectfully Art, there are people who will not ever hold with ideas that are considered mainstream. If *their* alternative ideas were accepted as fact, then there is an excellent chance that they will abandon them and move on to something else. This is especially true if feeling somehow come into their science. I see this fairly often. Politics often comes to mind, in which one group is excellent at castigation, pointing out example after example of others wrongdoing but when in power, they seem to not be able to effectively function. IOW, is the rebel right because they found out something new, and can promote the idea, or are they right because they are a rebel? Personal attacks were started years ago in an attempt to cut down the debate and all must resign themselves that the instant experts will defend the status quo for ever. I see personal attacks on both sides of the long drawn out arguments here. All are guilty. Will we ever see a painter sell his paintings for millions while he is still alive? I think there are more painters making millions than there are scientifically respected postings on usenet. - 73 de Mike N3LI - |
Standing-Wave Current vs Traveling-Wave Current
On 8 Jan, 06:39, Michael Coslo wrote:
art wrote: On 7 Jan, 10:15, Michael Coslo wrote: art wrote: Probably so. But pseudo experts such as Roy and Tom and the three Richards can't put o neck hold on the advances of science for ever, for people like MK to follow in lockstep in the absence of knoweledge. * * * * Crikeys, Art! How on earth are your nemeses strangling science? Does anyone in here take these bar room brawls seriously? * * * * I mean just what would this strangulation achieve? Does IEEE keep an archive of rraa? the National Science Foundation? * * * * These arguments, For all their sound and fury, signify nothing. I rather thought that they boys were all just feeling their oats. At any rate, the great unwashed such as myself find it all amusing. * * * * - 73 de Mike N3LI - In the scientific world it is a closed community and only within that community can members create change. * * * * This sounds like an indictment of the whole peer reviewed process. It's kind of like saying that People who have driver's licenses are a closed group. So you often hear that some very clever people did not have their ideas examined until after they were dead which can be a hundred years. * * * * Any cites here? Hams are a similar closed community with respect to what creates radiation since they only accept books and will not or cannot debate any alternatives. * * * * Here we really disagree! There is an amazing amount of antenna hokum scattered about among amateurs. When in college you are encouraged to debate which is way to retreat to the beginings and build up a case in opposition to the opponent.This cannot happen in ham radio because debates cannot happen except by those that deem themselves as experts whose mission is to protect the status quo Thus to become an expert one must follow the written word and deride those that deign to question the status quo.When was the last to you read of an open debate that was thouroughly discussed to a acceptable conclusion? Well you haven't heard one because when two heads debate one will always use personal attack as a means of retaliation.And I mean always. * * * * Art, here is where you make a huge mistake. You are bringing personal "feelings" into the equation. Who really gives a whoop doop dingle about feelings? * * * * With your Mechanical engineering background, I assume that you must have sat in on design and other meetings. Many of the ones I have sat in have become plenty heated. * * * * So What? We leave the meeting and go get the job done. Then we enjoy a beer with the people we were arguing with after work. There is one discussion on this newsgroup that has gone on for several years and thousands of postings about travelling waves which I for one consider them to be ficticious in a resonant system. Do you ever believe one side or the other will demonstrate the concepts *so all are on a common stage.? Hell no! * * * * Respectfully Art, there are people who will not ever hold with ideas that are considered mainstream. If *their* alternative ideas were accepted as fact, then there is an excellent chance that they will abandon them and move on to something else. This is especially true if feeling somehow come into their science. I see this fairly often. Politics often comes to mind, in which one group is excellent at castigation, pointing out example after example of others wrongdoing but when in power, they seem to not be able to effectively function. IOW, is the rebel right because they found out something new, and can promote the idea, or are they right because they are a rebel? Personal attacks were started years ago in an attempt to cut down the debate and all must resign themselves that the instant experts will defend the status quo for ever. * * * * I see personal attacks on both sides of the long drawn out arguments here. All are guilty. * Will we ever see a painter sell his paintings for millions while he is still alive? * * * * I think there are more painters making millions than there are scientifically respected postings on usenet. * * * * - 73 de Mike N3LI -- Hide quoted text - - Show quoted text - Things changed when the influx of CBers came into the hobby. As president of the local club it was my job to welcome them despite the animosity that was floating around. After 5 years I quit and watched as ham radio went down hill so I also quit getting on the air.As Age crept up on me I could not play around with mixers anymore so I chose antennas which my eyes could handle. I then got insulted when I shared what I was doing on this group as were my patents. I got so many insults that I even dropped one I had just applied for and left this newsgroup. I still carried on with my work and some years ago again shared it with the group. Insults immediately started coming thru without examining that I was sharing.But this time it is different. I am not going away even tho hams are not interested in new ideas and in fact push them away. True my writing gets worse as I age which is a sorry state of affairs butI am not willing to fade away. I WILL HANG ON AND STAY.I worked hard during the night scouring the internet to find a link that would explain part of the things that I talk about and which all reject and apply insults. I finally found a suitable site that also came with diagrams to make it easier to understand. It will be on another thread so please read it. If it is of interest then you will see I am not blabbering.Never the less I am willing to share the rest of my work with true radio amateurs that have the manners that are required for a suitable discussion or debate. Regards Art Unwin KB9MZ....XG ( uk) Art |
Standing-Wave Current vs Traveling-Wave Current
"Gene Fuller" wrote in message ... art wrote: WHY? bECAUSE THE MAGNETIC FIELD LINES FROM A DIAMAGNETIC MATERIAL SUCGH AS ALUMINUM OR COPPER IS AT RIGHT ANGLES TO THE AXIS OF CURRENT FLOW WHICH IS NOT THE SAME AS WITH A FERRITE MAGNETIC MATERIAL Does it matter that aluminum and copper are paramagnetic rather than diamagnetic? Perhaps you should consider a bismuth antenna. That is the poster child for diamagnetic metals. 73, Gene W4SZ oh, don't go getting all technical on him, he's having so much fun thinking he's pulling everyone's leg with his bafflegab... I get a good laugh out of it every day at least. |
Standing-Wave Current vs Traveling-Wave Current
Dave wrote:
ah, so once you have a standing wave on a line then no energy can cross the voltage or current nodes?? thats interesting. so at the place where current is 'always' 0 the voltage is a max right? so what happens to the V^2/Z power at that point? is that not flowing past that point? conversely, at the point where voltage is always zero, what happens to the large I^2*R power at that point??? where does that go? . . . You can see graphically exactly where the energy and power are at every point along the line at every instant, with the program I made for the purpose. It even separately shows the energy stored in the E and H fields. See the recent TLVis1 thread. Roy Lewallen, W7EL |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote:
I'd suggest that this is only if the concept of the waves in question does not include energy. In the limiting case of the two waves being identical no energy crosses the nodes. In other cases, only a portion of the energy crosses the nodes. If the concept of the waves includes energy, some explanation is required to account for the wave crossing the node, but its energy does not. Take a look at demo 4 with the TLVis1 program (described in the TLVis1 thread). Let it run to steady state, then single step. In the upper trace, look at one of the points where the power is always zero, i.e., where it crosses the center line. But as you step, you can see that the energy at that point increases and decreases with time. In fact, at some times it's zero and at other times it's one of the points of maximum energy density along the line. So how can this be? The power is always zero at that point, yet the energy is increasing and decreasing with time. The answer is that equal amounts of energy are moving to the right and left of that point at all times; energy is flowing into and out of that point equally from both sides. So although there are points where the power is always zero, those aren't the points where the energy isn't moving. There are, in fact, points along the line where the energy doesn't change with time, but they coincide with the points where the power is maximum. This simply means that, at those points, however much energy flows into a point flows out at any given time, leaving the total energy at those points constant. (Mathematically, this amounts to the existence of a constant when you integrate power to get energy.) So at all points along the open circuited line and at all times, energy is either moving, increasing, or decreasing. There aren't any static spots at all. I find it very helpful to look at this visually -- that's why I wrote the program. It also shows how misleading it is to mix power and energy. Some readers like to superpose energy just as they do voltage, but in general this is not a valid operation so I am uncomfortable using it as the explanation. I agree, you can't assign energy or power to the traveling waves separately and superpose them as you do voltage and current. TLVis1 calculates power and energy from the total voltage and current. Roy Lewallen, W7EL |
Standing-Wave Current vs Traveling-Wave Current
Roy Lewallen wrote:
... You can see graphically exactly where the energy and power are at every point along the line at every instant, with the program I made for the purpose. It even separately shows the energy stored in the E and H fields. See the recent TLVis1 thread. Roy Lewallen, W7EL My sisters' son has drawn some nice pictures on his bedroom wall with crayons--I can actually appreciate them--especially for his age--he does show some "artistic" leanings, in my humble opinion ... of course, I don't have to clean the crayon off the wall. I am sure your endeavors, at least, should enjoy such observations/considerations ... :-D Regards, JS |
Standing-Wave Current vs Traveling-Wave Current
Art wrote:
"This dust is what Gauss refers to as static particles in a gravitational field in equilibrium." What evidence do you have that gravity is related to static particles other than attracting their mass or that gravity affects radio waves significantly? Our universe may not have uniform acceleration, so are you sure about equilibrium? Maxwell did not need a medium for radio propagation. He was able to calculate the velocity of radio waves and believed that because it equaled the known speed of light his equations were correct. Best regards, Richard Harrison, KB5WZI |
Standing-Wave Current vs Traveling-Wave Current
Thanks for offering the two capacitor/one capacitor view of the middle
of the line. It took a bit of time to decide whether the commingling of the charge in the single capacitor at the middle of the line would solve my dilemma. So I considered this one capacitor in the exact center of a perfect transmission line. It is the perfect capacitor, absolutely symmetrical. So as the exactly equal currents flow into it on the exactly symmetrical leads, the charge is perfectly balanced so that the charge coming from each side exactly occupies its side of the conductor. As the two flows of charge flow over the perfectly symmetrical plates, they meet in the exact center, and flow no more. I conclude that a surface can be found exactly in the center of this capacitor across which no charge flows. Thus (un)happily returning me exactly to where I was before; there is a line across which no charge, and hence no energy, flows. More comments below. On Jan 2, 7:38 pm, Roy Lewallen wrote: I'm top posting this so readers won't have to scroll down to see it, but so I can include the original posting completely as a reference. Keith, you've presented a very good and well thought out argument. But I'm not willing to embrace it without a lot of further critical thought. Some of the things I find disturbing a 1. There are no mathematics to quantitatively describe the phenomenon. 2. I don't understand the mechanism which causes waves to bounce. I take this to imply that you are not happy with the simple "like charge repels"? 3. No test has been proposed which gives measurable results that will be different if this phenomenon exists than if it doesn't. (I acknowledge your proposed test but don't believe it fits in this category.) 4. I'm skeptical that this mechanism wouldn't cause visible distortion when dissimilar waves collide. But without any describing mathematics or physical basis for the phenomenon, there's no way to predict what should or shouldn't occur. 5. Although the argument about no energy crossing the zero-current node is compelling, I don't feel that an adequate argument has been given to justify the wave "bouncing" theory over all other possible explanations. I would really appreciate seeing some other possible explanations. One other one which I have seen and am not confortable with is the explanation that energy in the waves pass through the point in each direction and sum to zero. But this is indistinguishable from superposing power which most agree is inappropriate. As well, this explanation means that P(t) is not equal to V(t) times I(t), something that I am quite reluctant to agree with. The other explanation seen is that the voltage waves or the current waves travel down the line superpose, yielding a total voltage and current function at each point on the line which can be used to compute the power. With this explanation, P(t) is definitely equal to V(t) time I(t), which I do appreciate. The weakness of this explanation is that it seems to deny that the wave moves energy. And yet before the pulses collide it is easy to observe the energy moving in the line, and if a pulse was not coming in the other direction, there would be no dispute that the energy travelled to the end of the line and was absorbed in the load. Yet when the pulses collide, no energy crosses the middle of the line. Yet energy can be observed travelling in the line before and after the pulses collide. So... I can give up on pulses (or waves) moving energy. I am not happy doing that. I can give up on P(t) = V(t) * I(t). I am not happy doing that either. So the (poorly developped) "charge bouncing" explanation seems like a way out, but I certainly would appreciate other explanations for consideration. None of these make an argument with your logical development, although I think I might be able to do that too. But I'm very reluctant to accept a view of wave interaction that's apparently contrary to established and completely successful theory and one, if true, might have profound effects on our understanding of how things work. So frankly I'm looking hard for a flaw in your argument. And I may have found one. So I am not convinced that it any way goes against established theory. I have not seen established theory attempt an explanation of how the waves can both transport energy as well as not do so when waves of equal energy collide. A large part of the argument seems to revolve around a single point in a perfect transmission line, where the current is exactly zero. This is an infinitesimal point on a perfect line, so some anomalous things might be expected to happen there. Let's consider a transmission line as a huge number of series inductors and shunt capacitors, each an ideal lumped device. In the ideal case, of course, there would be an infinite number of each, and each would have an infinitesimal value. However, the LC product and ratio must remain correct even in the limiting case. Each L and C is an ideal device, so the current into one terminal of an inductor has to equal the current out of the other. A consequence of this is that either we have a whole inductor with zero current, or the zero current point occurs between inductors, at a node to which a capacitor is connected. I think we'll get the same result using either scenario, but let's consider the second. If we analyze this situation carefully, we'll find that the inductor on each side of the zero-current point does have a finite current, equal in amplitude and flowing in opposite directions. So for half of the cycle, both are putting positive charge in the capacitor, and for the other half of the cycle, both are removing charge. The capacitor voltage goes up and down as a result, as we can also see by looking at the voltage at this zero-current point. So current from both sides is contributing to the capacitor charge, and turning off either one would change the line conditions. Any change in the current from the inductor on one side would change the capacitor voltage, and hence the current on the other side. So there is an interchange of information from one side to the other. Each inductor is conveying energy to the capacitor, which is storing and returning it. Ok, so let's break the capacitor into two, each being half the original value, and constrain each inductor to deliver charge only to "its" capacitor. The wire between the capacitors carries no current because the capacitors always have equal voltages, and can be cut with no effect. When there was one capacitor, it shared energy from both sides. When we broke it into two, there was no mixing of energy from either side. Why might one be a better description of reality than the other? It looks to me like the argument devolves into speculation about how small the "point" is at which the current drops to zero. It is very, very small. It would be instructive to see what happens as, for example, the load resistance is increased toward infinity or decreased toward zero arbitrarily closely, but not at the point at which it's actually there. If the "bouncing" phenomenon is necessary only to explain the limiting case of infinite SWR on a perfect line but no others, then an argument can be made that it's not necessary at all. I suspect this is the case. The same concern that arises for pulses of equal voltage also occurs for pulses of different voltage. While the mid-point no longer has zero current, the actual current is only the difference of the two currents in the pulses, the charge that crosses is only the difference in the charge between the two pulses, and the power at the mid-point is exactly the power that is needed to move the difference in the energy of the two pulses. So the challenge is not so starkly obvious as it is when the power at the mid-point is always 0, but P(t) = V(t) * I(t) can still be computed and it will not be sufficient to allow the energy in the two pulses to cross the mid-point (unless one likes superposing power, in which case it will be numerologically correct). I agree with your argument about two sources energized in turn, and have used that argument a number of times myself to refute the notion of superposing powers. Once two voltage or current waves occupy the same space, the only reality is the sum. We're free to split them up into traveling waves or any other combination we might dream up, with the sole requirement being that the sum of all our creations equals the correct total. (And the behavior of waves you're describing seemingly go beyond this.) I sometimes think that this may actually be a debate about the conceptual view of waves. If waves consist only of voltage and current, then all is well, superposition works, the correct answers are achieved. And if the power is computed after the voltages and currents are arrived at, all is well. But if one conceives waves as also including energy, then it seems that the question 'where does the energy go' is valid and the common explanations do not seem to hold up well. The advantage to the non-interacting traveling wave model is that it so neatly predicts transient phenomena such as TDR and run-up to steady state. I spent a number of years designing TDR circuitry, interfacing with customers, and on several occasions developing and teaching classes on TDR techniques, without ever encountering any phenomena requiring explanations beyond classical traveling wave theory. So you can understand my reluctance to embrace it based on a problem with energy transfer across a single infinitesimal point in an ideal line. Yes, indeed. Though any (new) explanation would have to remain consistent with the existing body of knowledge which works so well. ....Keith Roy Lewallen, W7ELKeith Dysart wrote: On Dec 30 2007, 6:18 pm, Roy Lewallen wrote: Keith Dysart wrote: [snip] |
Standing-Wave Current vs Traveling-Wave Current
On 10 Jan, 10:48, (Richard Harrison) wrote:
Art wrote: "This dust is what Gauss refers to as static particles in a gravitational field in equilibrium." What evidence do you have that gravity is related to static particles other than attracting their mass or that gravity affects radio waves significantly? I amnot sure how they came into the earths atmosphere but Gauss has them placed in a field in equilibrium. I do not believe and I have not said that earths gravity has any affect on propagation. Remember, the static particles have a very weak anti gravity force which nullifies the earths gravitational or magnetic forces. Thus the static particles can take a straight line velocity. Our universe may not have uniform acceleration, so are you sure about equilibrium? Yes I am. That is a basic for a Pointings vector and most certainly for Gauss. Both of these analysis are dependent on the gravitational field being spherical so the calculations have to be modified slightly because out earth is lemon shape but it is close enough for calculations Maxwell did not need a medium for radio propagation. He was able to calculate the velocity of radio waves and believed that because it equaled the known speed of light his equations were correct. Well his equations are correct as are the laws that he condensed. Lorenz law however was on the basis of deduction or observance which turned out to be correct but there were no details for Maxwell to hang on to which leaves all as a very difficult puzzle I started the aproach of continuing Gausses work on static which the books seem to relate as a subset of electro magnetics. So I added a time varient to a static field which provided a direct connection to Maxwells laws. Thus at this point I accept the static particles at rest and inserted a radiator in the field which ofcourse must be resonant and in equilibrium so it didn't upset the Gaussian field. When this was done we have a dynamic field from which we can draw the statement that a radiator made from a diamagnetic material can be any \hape, size elevation e.t.c as long as it is in equilibrium. Thus this observation or deduction states that a helical antenna is not in equilibrium unles the windings have balancing contra windings. Thus any wound design such as EH ntennas or Vincent antenna must have contra windings to be in equilibrium and thus fully efficient. Armed with the above I placed a radiator into a computor program with an optimizer and confirmed the above i.e. it was not planar. So why was the element tipped from parallel to the earths surface? If you make a vector analysis of a radiator with it's many vectors the resultant single vector is not parallel to the axis of the radiator. In addition I look at a helical design and not that the pitch angle is the same found by Kraus experimentally was the same angle as the resultant vector of a radiator. We then examine the radiator with a static particle at rest on it's surface and then make a electri9cal circuit of what we see. The result for equilibrium must be a tank circuit where all enrgy is interchanged between the energy storage tanks( inductance and capacitance) Both of these expend there energy as if the terminals were shorted, and who hasn't shorted a capacitor to generate an explosion.One can imagine a explosive force sliding or lifting the static particles to the inductor reciever which because the material is diamagnetic the lines of force of the magnetic field will levitate or thrust the particles away from the radiator. Using Newtons law we can see that the reactionary force of the ejected particles will imping on the radiator itself ad make it occilated. Of course the particles are many and the number of periods in the frequency applied is like generating a horrendous number of samples of oscillation, much more than the human ear does and these samplers will then apply a mirror image of the occillationd to the recieving radiator. So like a jigsaw puzzle the measure of difficulty in solving the given problem is determined by the starting point. And tho I manipulated Gauss to a Maxwell form which was the same masthematical law,as with all things it is not only the destination that counts but everything one observes on the way. The bottom line is that for best efficiency for the unit volume supplied an array must be in equilibrium. Thus distances between radiators become smaller and elements which can be helically wound is also shorter and by virtue of the array not being planar we have a single feed plus the "stacked"gain. I have not made an array but I have made many helical designs and the like.Programs confirm these as being legitamate. The fact that I modified the static law to a dynamic law is the only thing that is "different". Every other action along my travels are extensivly studied in the books tho not relavent to radiation. I say again, the complexity depends on where you start and I did not view static as a subset like the books do. Art Unwin KB9MZ...XG Best regards, Richard Harrison, KB5WZI |
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