|
Standing-Wave Current vs Traveling-Wave Current
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? I've used SPICE to verify my analysis. If I modify the SPICE model to show the voltage just inside the line, do you think it will show the voltage to be 2*sin(wt)? SPICE makes no assumptions about waves, bouncing or not, so if it shows sin(wt) (as it certainly will), where do you think its error is? Roy Lewallen, W7EL |
Standing-Wave Current vs Traveling-Wave Current
Cecil Moore wrote:
Gene Fuller wrote: The entire point of s-parameter analysis is that the "network" can be treated as a black box, ... Gene, I cannot find anywhere in the s-parameter information where some of the network must be hidden inside a black box. I always thought an s-parameter analysis could be done without a black box. Could you help us out here and point out exactly where it says a black box is a requirement. Seems to me the purpose of an s-parameter analysis is to alleviate ignorance which obviously doesn't match your agenda. Why don't you try your favorite s-parameter reference, AN 95-1, page 6? Since you are playing words games again by changing "can be treated" into "requirement", I suppose you already are well aware of what AN 95-1 says. 73, Gene W4SZ |
Standing-Wave Current vs Traveling-Wave Current
Gene Fuller wrote:
My definition of "sloshing" is as I stated. Look up "slosh" in the dictionary and then get back to us. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Roger wrote:
By my using the words 'power' "storage factor", you got my point, hence the reaction. Before dismissing the concept of "storing power", consider that when discussing a transmission line, it could be a useful description. As you know, power is energy delivered over a time period. No, it's the rate of energy delivery or movement, which is not quite the same thing. It always carries a time dimension having beginning and end. Power(watt) =v*i/(unit time) = 1 joule/second. Sorry, you've got this wrong. One watt is indeed one joule/second, but P(t) = v(t) * i(t), period. Energy is the integral of P(t) dt. Power is the time derivative of energy, or dE(t)/dt where E is the energy. You could as reasonably say that energy always "carries a time dimension". After all, one joule = 1 watt-second. In the example you give of charging a capacitor, the time dimension is lost, so you are correct that only energy is conserved. Power is lost. Sorry, I don't understand that. With a transmission line, we have an entirely different case. Here power is conserved because the time information is maintained. Power is stored on the line during the period it resides on the line. For example, we excite the line at one end and some time period later find that power is delivered to some destination. During the time period that the power was on the line, the information that defines the energy distribution over time has been preserved. Ok, let's test this. Please tell me exactly how many watts are stored on the line of the second analysis (where the perfect source is in series with a 150 ohm resistor). Next, tell me how many watts will come out of the line if we quickly disconnect the perfect source and source resistance and replace it with: A: A 50 ohm resistor, or B: A 150 ohm resistor If power is stored, we implicitly store energy. Energy is v*i measured in joules without a time factor. No, Energy is not v*i. Power is v*i. Energy is the time integral of v*i. Power is not stored; energy is. Obviously we store energy on a transmission line when we store power. I guess it would be obvious if you believe you can store power. But before going further, please demonstrate what you mean by calculating how many watts of power are stored on the example line. I showed exactly how many joules of energy were stored, you can show how many watts of power. So if in the future, I use the term "power storage", please take it to mean that energy distributed over time is under consideration. I'm afraid I'm not very good at translating what people mean when they say something else. Why not call energy storage "energy storage", power "power", and energy "energy"? Then I and hopefully other readers will know what you mean. The MKSA unit of power is the watt, and of energy, the joule. The two are no more the same than speed and distance, or charge and current. I hope the term might be useful to you as well. No, I have enough trouble communicating when I take great care with my terminology. The last thing I need is to be saying something which means something else -- or means nothing at all. When I mean energy storage, I'll say "energy storage", thank you. Roy Lewallen, W7EL |
Standing-Wave Current vs Traveling-Wave Current
Gene Fuller wrote:
I suppose you already are well aware of what AN 95-1 says. Yes, nowhere can I find where a black box is required for the purpose of hiding part of the system from the observer. When a concept is used to alleviate ignorance, it is good. When a concept is used to promote ignorance, it is bad. What you are trying to do is pretty obvious. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Gene Fuller wrote:
Cecil, If your only concern is the definition of "sloshing", then about 100,000 messages have been wasted. My definition of "sloshing" is as I stated. I believe that Roy would have the same definition. If your definition involves the speed of water, then I have no idea why that topic would be relevant here. I've used the term a few times in this forum, and in the context exactly as you explained, clearly, in your previous posting. And as I also have explained several times in this forum since I first used it to describe energy in a line with infinite SWR in a posting in December 2002. But you can fully expect to see the question asked again and again as it has been over the intervening five years. This is a good example of the reason I plonked Cecil some time ago. I don't see Cecil's postings unless quoted by someone else, nor do I consider it anything but a waste of time and cause of pointless frustration to respond to him unless the answer would also potentially benefit other readers. So no one should interpret my lack of response to anything he directs to me as any sort of endorsement or agreement. Roy Lewallen, W7EL |
Standing-Wave Current vs Traveling-Wave Current
Roy Lewallen wrote:
I've used the term a few times in this forum, and in the context exactly as you explained, clearly, in your previous posting. You really should have looked up the definition in the dictionary before willy-nilly using it. FYI, it is impossible for EM energy to slosh. I don't see Cecil's postings unless quoted by someone else, nor do I consider it anything but a waste of time and cause of pointless frustration to respond to him unless the answer would also potentially benefit other readers. So no one should interpret my lack of response to anything he directs to me as any sort of endorsement or agreement. You still haven't posted the equation for standing wave current and explained how you used that current to make your phase/delay measurements through a 75m bugcatcher loading coil. Pretty convenient that you can ignore my postings, huh? -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
On Thu, 03 Jan 2008 20:58:52 GMT, Cecil Moore
wrote: Richard Clark wrote: There is a vast gulf between seeming and proving. Richard, you seem to exist. Please prove that you indeed do exist. Gad, with built-in failures of logic like this question, it is SO, SO easy, I can do it in stereo: First, I can pinch myself: corporeal reality! However, you are just amusing words on a screen that I can erase at will, hence you are a figment of the imagination - the essential seeminess. Second (this is the same mystery investigated as the Chinese Room Argument), your messages only appear to be intelligent. Subsequent correspondence reveals that to be a fiction. What a pair of slam dunks for the home team. Want to go for the trifecta? Both the first and second tests can be independently corroborated by a multitude of other posters here! Dubito Tu Es |
Standing-Wave Current vs Traveling-Wave Current
On Thu, 03 Jan 2008 17:58:51 -0600, Cecil Moore
wrote: Pretty convenient that you can ignore my postings, huh? You still haven't demonstrated how to balance the energy equations for a battery in one pocket, and a mouse in the other. Pretty convenient that you can ignore my postings, huh? |
Standing-Wave Current vs Traveling-Wave Current
Richard Clark wrote:
... You still haven't demonstrated how to balance the energy equations for a battery in one pocket, and a mouse in the other. Pretty convenient that you can ignore my postings, huh? Remove the Dick in the way? They do call you Dick for short, don't they? ROFLOL JS |
Standing-Wave Current vs Traveling-Wave Current
Gene, W4SZ wrote:
"Some people like to treat standing waves as poor distant cousins to "real" waves, or perhaps as "only envelopes"." Frederick J. Bueche & Eugene Hecht may have said it best in "Schaum`s College Physics Outline": "Standing waves---These might better not be called waves at all since they do not transport energy and momentum." Best regards, Richard Harrison, KB5WZI |
Standing-Wave Current vs Traveling-Wave Current
|
Standing-Wave Current vs Traveling-Wave Current
On Jan 3, 12:55*pm, Mike Monett wrote:
* Keith Dysart wrote: * [...] * You did *not directly answer Q1, but I take if from all *the other * responses that *you *are *saying *the answer *is *"no, *it *is not * appropriate to view a transmission line as distributed capacitance * and inductance *and analyze its behaviour using *charge *stored in * the capacitance and moving in the inducatance?" * That is not what you originally stated. * Taking this *invalidates all the subsequent *questions *since they * are based *on *the * premise * that * this * kind *of *analysis is * appropriate. * Yes, it does. * 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. 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. 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. ...Keith |
Standing-Wave Current vs Traveling-Wave Current
On Jan 3, 1:25*pm, Cecil Moore wrote:
For the record: The only controversial assertion that I have ever made is that coherent EM wave cancellation can cause a redistribution of the EM energy in the opposite direction in a transmission line. Don't be so modest. You have also claimed that for an amplifier which can be modelled as a Thevenin or Norton equivalent circuit, the output impedance can not be used to derive the reflection coefficient. You have claimed that the only way to prevent a re-reflection at a generator is to use a circulator; a 10 cent resistor will never do. You have claimed that energy can cross a point on the line where V or I is always 0. You have claimed that there is great importance to the terms "Traveling-Wave Current" and "Standing-Wave Current" (the title of this thread). And there were more that escape my memory. ...Keith |
Standing-Wave Current vs Traveling-Wave Current
On Jan 3, 2:14*pm, Jim Kelley wrote:
Keith Dysart wrote: The example was carefully chosen to illustrate the point, of course. But that is the value of particular examples. When the pulses are not identical, the energy that crosses the point is exactly sufficient to turn one pulse into the other. The remainder of the energy must bounce because it does not cross the mid-point. ...Keith So it really is almost as though the pulses travel through one another, rather than bounce off one another. I have seen the concept that energy doesn't cross nodal points alluded to in some texts. *However there are so many exceptions to it found in physical systems as to render it a dubious notion at best. Useful perhaps for illustration purposes. In the discussion of standing waves on a string, Halliday and Resnick says "It is clear that energy is not transported along the string to the right or to the left, for energy cannot flow past the nodal points in the string, which are permanently at rest. *Hence the energy remains "standing" in the string, although it alternates between vibrational kinetic energy and elastic potential energy." So the idea is valid for a simple harmonic oscillator in which there are no losses. *In such a case, once the system begins oscillating, no further input of energy is required in order to maintain oscillation. * Clearly there is no flow of energy into or out of such a system. What is clear is that energy doesn't pass through the nodes. *It is less clear that there exists an inherent mechanism which prevents the movement of energy. And so it appears in cases where there is no transfer of energy that one might claim that waves bounce off of one another. *There are no other examples, and no supporting mechanism for it of which I am aware, and so one might be equally justified in claiming that waves pass through each other in all cases. 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. 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. ...Keith |
Standing-Wave Current vs Traveling-Wave Current
"Keith Dysart" wrote in message ... Sorry i have been absent for a while, been too busy with other work and had to turn this off to keep from spending all my time laughing at the postings. Are we going for another 1000 post thread? almost 2/3's of the way there now... here is a kick to keep it going. You have claimed that energy can cross a point on the line where V or I is always 0. 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? then try this thought experiment... take a long coax with an open circuit end, feed it with sinusoidal ac so it has nice standing waves, keep it lossless just because that irritates some of the writers on here. then attach a pure resistance equal to Z0 at the open end. now, if energy can't pass the points where V or I is zero, and I is obviously zero at the open circuit at the end of the line there should be no power to flow into that resistor??? Oh, but wait, the voltage is a max there so the resistor could draw power from the voltage standing wave, but then what happens to the current standing wave? once the resistor drains the last half wave voltage wave how does energy get from the next standing wave into the far end one to replenish it if it can't flow across the voltage node?? sorry, i have to stop, about to start another laughing fit. all of the above obvious contradictions become intuitively obvious once you completely forget the standing waves and think only in terms of the traveling waves. and remember, again just because it tweaks some correspondents on here, you only need the voltage OR the current traveling wave, either one is sufficient to completely describe the conditions on the line in either steady state or transient conditions. (as long as the line and components are all linear and time invarient, loss is not a problem for this statement to be true) |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote:
And yet I commonly see discussion of current in transmission lines. RF current is a *result* of the H-field in the EM wave. There are photons involved making it different from DC. Electrons may (or may not) "bounce" off of each other but photons traveling in opposite directions in a transmission line do not and cannot "bounce" off of each other. They pass each other like ships in the night. Any theory based on photons "bouncing" off of each other while traveling in opposite directions, is inaccurate and doomed to failure. Simply applying the scientific method will remedy the problem. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
cecil scribbled:
RF current is a *result* of the H-field in the EM wave. There are photons involved making it different from DC. which comes first, the current or the field? i contend that it is not necessary to consider the current or the h-field at all. use the voltage traveling wave and it is not necessary to consider current at all, hence where does the h-field come from? or consider the current traveling wave and then where does the e-field come from? forget photons when thinking of coax, antennas, currents, and waves, they will just confuse you. |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote:
You have also claimed that for an amplifier which can be modelled as a Thevenin or Norton equivalent circuit, the output impedance can not be used to derive the reflection coefficient. And have proved it with concepts that existed before I was born. I cannot take credit for that. If an amplifier is delivering zero net power, the calculated rho = SQRT(Pref/Pfor) = plus or minus 1.0 The value of the "output impedance" is irrelevant. Because of superposition, the reflected energy never encounters the "output impedance". You have claimed that the only way to prevent a re-reflection at a generator is to use a circulator; a 10 cent resistor will never do. Roy has said essentially the same thing in so many words. You see, your concepts lead to a direct violation of the conservation of energy principle for which I can take no credit. You have claimed that energy can cross a point on the line where V or I is always 0. Since it is impossible for photons to reflect while traveling in a homogeneous medium, that one is a no-brainer. I cannot take credit for anything I learned from Quantum Electrodynamics. You have claimed that there is great importance to the terms "Traveling-Wave Current" and "Standing-Wave Current" (the title of this thread). Again, I didn't invent standing wave current and traveling wave current. I am just reporting what I have learned from people who knew the difference before I was born. If one knows much of anything about mathematics, one can look at the equation for standing wave current and the equation for traveling wave current and see the considerable differences. That you cannot just proves that you don't know much of anything about mathematics. Standing wave current = Io*cos(kx)*cos(wt) Traveling wave current = Io*cos(kx+wt) I feel sorry for any "technical" person who cannot see the difference. For traveling waves, the position and phase are interlocked. For standing waves, the position and phase are divorced. Those differences are obvious and are plotted at. http://www.w5dxp.com/travstnd.gif -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote:
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. Optical physicists have been "adding" power densities (irradiance) for centuries. It's past time for you to learn how they did it. -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Cecil Moore wrote:
... RF current is a *result* of the H-field in the EM wave. There are photons involved making it different from DC. Electrons may (or may not) "bounce" off of each other but photons traveling in opposite directions in a transmission line do not and cannot "bounce" off of each other. They pass each other like ships in the night. Any theory based on photons "bouncing" off of each other while traveling in opposite directions, is inaccurate and doomed to failure. Simply applying the scientific method will remedy the problem. This thread has become long, it is so long--everyone must have some sort of questions--or it (the thread) has prompted some sort of question(s) in their minds'. If not, so be it, I am a "weirdo" for it ... 1) Does a .0001 Hz signal use photons? A .001 Hz? A .01 Hz? A .1 Hz? A 1 Hz? I mean, at what "magical point" do photons become involved? 2) What experiment(s) have "seen" these photons? A fogging of film emulsion? ??? In all seriousness, I simply have a problem with photons doing much more than "vibrating in near-place." With light, I can imagine photons ... Warm regards, JS |
Standing-Wave Current vs Traveling-Wave Current
Dave wrote:
forget photons when thinking of coax, antennas, currents, and waves, they will just confuse you. Keith has taken your advice to forget photons. Why is he confused? -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
John Smith wrote:
1) Does a .0001 Hz signal use photons? A .001 Hz? A .01 Hz? A .1 Hz? A 1 Hz? I mean, at what "magical point" do photons become involved? Already answered. Any time electrons are accelerated or decelerated, photons are involved. Any frequency of AC can provide electron acceleration and deceleration. 2) What experiment(s) have "seen" these photons? A fogging of film emulsion? ??? Process of no-brainer elimination: Nothing else besides photons can travel at the speed of light in a transmission line (adjusted for the VF of the medium). -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Cecil Moore wrote:
John Smith wrote: 1) Does a .0001 Hz signal use photons? A .001 Hz? A .01 Hz? A .1 Hz? A 1 Hz? I mean, at what "magical point" do photons become involved? Already answered. Any time electrons are accelerated or decelerated, photons are involved. Any frequency of AC can provide electron acceleration and deceleration. 2) What experiment(s) have "seen" these photons? A fogging of film emulsion? ??? Process of no-brainer elimination: Nothing else besides photons can travel at the speed of light in a transmission line (adjusted for the VF of the medium). Cecil: I look for no fight, sometimes I just have "too much fun", sometimes at others expense ... I really mean no harm ... I just don't know ... I'll keep my mind open. "No-brainer?" Huh, I'll work on increasing the "gray matter" here. I'll check what's available in the health food stores. :-P Regards, JS |
Standing-Wave Current vs Traveling-Wave Current
As always, I very much appreciate the education provided by Roy.
It seems to me that much of the problem here is the continuous misunderstanding of the difference between "power" and "energy". What is difficult for me to understand is the sustained misunderstanding, even after the definitions have been reviewed time and time again. Bill - W2WO |
Standing-Wave Current vs Traveling-Wave Current
John Smith wrote:
"No-brainer?" No-brainer for anyone who knows what particles are available inside a transmission line. Sorry for being short. My daughter is having emergency surgery today and I am preparing for a trip to warm sunny Syracuse, NY. :-( -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
Richard Clark wrote:
"Does a surfer violate this definition?" Traveling waves carry surfers to the beach. Standing waves only oscillate the water surface up and down in place. Best regards, Richard Harrison, KB5WZI |
Standing-Wave Current vs Traveling-Wave Current
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 full wave length and equates with 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 eaths 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. 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. 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. Best Regards Art Unwin.....KB9MZ...XG (uk) |
Standing-Wave Current vs Traveling-Wave Current
On Fri, 4 Jan 2008 04:02:23 -0800 (PST)
Keith Dysart wrote: On Jan 3, 2:14*pm, Jim Kelley wrote: Keith Dysart wrote: The example was carefully chosen to illustrate the point, of course. But that is the value of particular examples. When the pulses are not identical, the energy that crosses the point is exactly sufficient to turn one pulse into the other. The remainder of the energy must bounce because it does not cross the mid-point. ...Keith So it really is almost as though the pulses travel through one another, rather than bounce off one another. I have seen the concept that energy doesn't cross nodal points alluded to in some texts. *However there are so many exceptions to it found in physical systems as to render it a dubious notion at best. Useful perhaps for illustration purposes. In the discussion of standing waves on a string, Halliday and Resnick says "It is clear that energy is not transported along the string to the right or to the left, for energy cannot flow past the nodal points in the string, which are permanently at rest. *Hence the energy remains "standing" in the string, although it alternates between vibrational kinetic energy and elastic potential energy." So the idea is valid for a simple harmonic oscillator in which there are no losses. *In such a case, once the system begins oscillating, no further input of energy is required in order to maintain oscillation. * Clearly there is no flow of energy into or out of such a system. What is clear is that energy doesn't pass through the nodes. *It is less clear that there exists an inherent mechanism which prevents the movement of energy. And so it appears in cases where there is no transfer of energy that one might claim that waves bounce off of one another. *There are no other examples, and no supporting mechanism for it of which I am aware, and so one might be equally justified in claiming that waves pass through each other in all cases. 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. 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. ...Keith Food for thought. Consider an isolated transmission line charged to some DC voltage. Then initiate current by attaching a resistor. We can identify a wave moving back from the junction, beginning at the time of contact. We can also, by monitering the current or power through/into the resistor, plot a wave going through/into the resistor. The two waves would be mirror images of one another. The forward wave would clearly carry energy, the backmoving wave would be a "book keeping" wave that reported the energy removed from the transmission line. The bookkeeping wave would really be the visible part/result of a power wave that is the negative equivalent of the wave passing through the resistor. Mathematically defining the energy component of the power wave, we should have If*Ef = 1 - Ib*Eb, where If and Ef are the instantaneous measured values of forward current and voltage, and Ib and Eb are the instantaneous measured values of bookkeeping current and voltage. The number 1 defines the beginning energy level as 1. We should observe that If = Ir. If so, then Ef = 1 - Er. Remember, these would be instantaneous values. 73, Roger, W7WKB |
Standing-Wave Current vs Traveling-Wave Current
Correction. Made a typo on the math equation.
On Fri, 4 Jan 2008 09:47:59 -0800 Roger Sparks wrote: On Fri, 4 Jan 2008 04:02:23 -0800 (PST) Keith Dysart wrote: On Jan 3, 2:14*pm, Jim Kelley wrote: Keith Dysart wrote: The example was carefully chosen to illustrate the point, of course. But that is the value of particular examples. When the pulses are not identical, the energy that crosses the point is exactly sufficient to turn one pulse into the other. The remainder of the energy must bounce because it does not cross the mid-point. ...Keith So it really is almost as though the pulses travel through one another, rather than bounce off one another. I have seen the concept that energy doesn't cross nodal points alluded to in some texts. *However there are so many exceptions to it found in physical systems as to render it a dubious notion at best. Useful perhaps for illustration purposes. In the discussion of standing waves on a string, Halliday and Resnick says "It is clear that energy is not transported along the string to the right or to the left, for energy cannot flow past the nodal points in the string, which are permanently at rest. *Hence the energy remains "standing" in the string, although it alternates between vibrational kinetic energy and elastic potential energy." So the idea is valid for a simple harmonic oscillator in which there are no losses. *In such a case, once the system begins oscillating, no further input of energy is required in order to maintain oscillation. * Clearly there is no flow of energy into or out of such a system. What is clear is that energy doesn't pass through the nodes. *It is less clear that there exists an inherent mechanism which prevents the movement of energy. And so it appears in cases where there is no transfer of energy that one might claim that waves bounce off of one another. *There are no other examples, and no supporting mechanism for it of which I am aware, and so one might be equally justified in claiming that waves pass through each other in all cases. 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. 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. ...Keith Food for thought. Consider an isolated transmission line charged to some DC voltage. Then initiate current by attaching a resistor. We can identify a wave moving back from the junction, beginning at the time of contact. We can also, by monitering the current or power through/into the resistor, plot a wave going through/into the resistor. The two waves would be mirror images of one another. The forward wave would clearly carry energy, the backmoving wave would be a "book keeping" wave that reported the energy removed from the transmission line. The bookkeeping wave would really be the visible part/result of a power wave that is the negative equivalent of the wave passing through the resistor. Mathematically defining the energy component of the power wave, we should have If*Ef = 1 - Ib*Eb, where If and Ef are the instantaneous measured values of forward current and voltage, and Ib and Eb are the instantaneous measured values of bookkeeping current and voltage. The number 1 defines the beginning energy level as 1. We should observe that If = Ir. If so, then Ef = 1 - Er. Remember, these would be instantaneous values. Please correct the math typo. If if = Ir, then Ef = 1/Ef - Eb 73, Roger, W7WKB -- Roger Sparks |
Standing-Wave Current vs Traveling-Wave Current
Cecil Moore wrote:
... No-brainer for anyone who knows what particles are available inside a transmission line. Sorry for being short. My daughter is having emergency surgery today and I am preparing for a trip to warm sunny Syracuse, NY. :-( I wish you and the daughter well. I wouldn't wish NY on anyone, indeed, California neither! I have three sons, I can empathize more than you can imagine ... no offense taken, my skin is much thicker than that. Take care of the family, this can all continue at a later date ... Regards and good luck, JS |
Standing-Wave Current vs Traveling-Wave Current
art spewed:
So you see the reason why aluminum is used for radiators because they belong to a familly known as diamagnetic material. so art, how do my steel tower 80m 4-square verticals work? how do most AM broadcast towers that are all steel radiate? 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?? |
Standing-Wave Current vs Traveling-Wave Current
On 3 Jan, 12:29, (Richard Harrison) wrote:
Art wrote: "It is obvious that the completion of a cycle thus at no time has current moving other than in a single direction." We have a "cycle" because the current alternates or reverses direction twice each cycle. Geez. What is the matter with you? Ofcource A.C reverses direction. I know you will fight change but in no way does that change anything other than we don't have a lot of things bouncing around like this long thread is suggesting as well as you . Hams likely agree with Terman that radio waves are produced to some extent whenever a wire in open space carries a high-frequency current. (Page 864, opus of 1955) Ofcourse hams are aware that radio waves are produced when a wire is subject to a alternating current. They have normally call this wire a antenna or a radiator. Nothing special there either. What is your message OM? Kraus says on page 12 in the 3rd edition of "Antennas": "Antennas convert electrons to photons, or vice versa." He could be correct in that opinion! there are many opinions out there including mine but other theories have not been established by previously known facts Also: "Thus, time-changing current radiates and accelerated charge radiates." Richard, it is a basic fact that a time varying field creates radiation and I have explained in detail the sequence of events. I have NO problem with you debating a fact that I have given or even supply a equivalent sequal of events supplied by another that implicitly contradicts what I have written but you are just supplying words. Again what is your message?Spit it out please. Also: The currents on the transmission line flow out on the antenna and end there, but the fields associated with them keep on going. No silly. When the current stops decay begins. We have not found a means for perpetual energy as far as I know. Current flow in a parallel circuit is maintained by a generator which re supplies energy that is lost in the circuit. When you turn off the generator the current flow stops. I really am not interested on what could happen when you turn the power off I just walk away and why not? I wish Richard you would stop putting spam on this thread Surely there are other things for you to do in life other than dropping names and inane suggestions which by their very nature donot require a response. You are just copying the antics of the other Richards trying to taunt as if you are afraid of something which you want to put down. Why not find a truth and the use it to debate a position? That is called a debate or a conversation? There is no nead to bait and taunt. Art Unwin KB9MZ....XG Best regards, Richard Harrison, KB5WZI |
Standing-Wave Current vs Traveling-Wave Current
Richard Harrison wrote:
Richard Clark wrote: "Does a surfer violate this definition?" Traveling waves carry surfers to the beach. Standing waves only oscillate the water surface up and down in place. Best regards, Richard Harrison, KB5WZI Richard, A few questions: * Have you ever seen a surfer? * Did you perhaps notice that the surfer typically travels much faster than the water? * Did you ever think that is why the boards are shaped the way they are? * Did you ever wonder how the surfer moves around if he or she is only riding on the moving water? * Did you ever see one of those surfer parks where folks surf on man-made waves that stay in one place? * Do you think perhaps the slope of the water might be important? * Does a traveling wave have a different slope than a standing wave? What does Terman say about all of this? 73, Gene W4SZ |
Standing-Wave Current vs Traveling-Wave Current
On 4 Jan, 10:31, "Dave" wrote:
art spewed: So you see the reason why aluminum is used for radiators because they belong to a familly known as diamagnetic material. so art, how do my steel tower 80m 4-square verticals work? *how do most AM does broadcast towers that are all steel radiate? It has a galvanised skin which is a diamagnetic material. Just like aluminum current fliows on the surface. But Dave you surely knew that so why did you place the question ? Are you joining the Richard trio and try to spam any thread out of existance that you dislike? We already have plenty of spammerrs on all of the Radio newsnets. You and the other spammers would do ham radio a real favor if you generated your own newsgroup for comment rather than clogging all the threads on the newsgroups. Art |
Standing-Wave Current vs Traveling-Wave Current
Cecil Moore wrote: Optical physicists have been "adding" power densities (irradiance) for centuries. Yes, but physicists who publish in scientific journals and textbooks tend to be more careful in their calculations than are people who publish on the internet. That is why text books are generally considered reliable sources, whereas the internet newsgroups (where people can write whatever they please without consequence) are generally not. 73, ac6xg |
Standing-Wave Current vs Traveling-Wave Current
Keith Dysart wrote: On Jan 3, 2:14 pm, Jim Kelley wrote: And so it appears in cases where there is no transfer of energy that one might claim that waves bounce off of one another. There are no other examples, and no supporting mechanism for it of which I am aware, and so one might be equally justified in claiming that waves pass through each other in all cases. 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. 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. ...Keith Hi Keith, I'd like to thank you for your thoughtful and courteous post. I agree with your observation about superposition of energy [and power]. In fact this would seem to lend support to the idea that there can be no 'energy nodes' on a transmission line. Question for you: can you reference a thermodynamic treatment of this concept of 'energy not crossing a node'? I think that thermo should relate to just about energy transfer issue we might want to discuss, including electromagnetic energy. Thanks, Jim Kelley, AC6XG |
Standing-Wave Current vs Traveling-Wave Current
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. :-) -- 73, Cecil http://www.w5dxp.com |
Standing-Wave Current vs Traveling-Wave Current
art continued spewing:
It has a galvanised skin which is a diamagnetic material. Just like aluminum current fliows on the surface. But Dave you surely knew that so why did you place the question ? not all tower is galvanized, some is simply painted... but art, you surely knew that, so why make that assumption. Just to prove you wrong i just stuck a piece of old iron wire, rust and all, in the connector for my ht and miracle of miracles, it still transmits! oh, and those cosmic dust particles, do they settle on antennas that are inside buildings or under radomes? do they get blown off in the wind or fly off when a car with an antenna goes around a tight corner?? |
Standing-Wave Current vs Traveling-Wave Current
Jim Kelley wrote:
Cecil Moore wrote: Optical physicists have been "adding" power densities (irradiance) for centuries. Yes, but physicists who publish in scientific journals and textbooks tend to be more careful in their calculations than are people who publish on the internet. That is why text books are generally considered reliable sources, whereas the internet newsgroups (where people can write whatever they please without consequence) are generally not. Jim, you are posting to an internet newsgroup so does that automatically make your posting equivalent to the lowest layer of whale s__t in the deepest part of the ocean? :-) Please tell us exactly what is wrong with the irradiance equation published in Born & Wolf and "Optics", by Hecht. -- 73, Cecil http://www.w5dxp.com |
| All times are GMT +1. The time now is 07:17 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com