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Cecil Moore wrote: Jim Kelley wrote: You do understand what a standing wave pattern is, right? At any instant of time at a standing wave current maximum point (loop, antinode), the charge carriers are either moving toward the load (ends of the dipole) or toward the source (feedpoint). You do understant that a standing wave pattern is NOT a plot of instantaneous voltages or currents, right? 73, Jim AC6XG |
Jim Kelley wrote:
Cecil Moore wrote: Current cannot stand still. You keep saying that as if it was relevant. It is relevant to the logical corner into which you have painted yourself. There exists current at the base of a coil. It either flows into the coil or away from the coil. There is simply no other place for it to go since it cannot stand still. Both in to and out of. Not one or the other. You are forgetting your conventions. If the current at the bottom of the coil is in phase with the feedpoint current, it is flowing the same direction as the feedpoint current. By convention, the feedpoint current is assumed to be flowing *into* the antenna. Therefore, by convention, the in-phase current at the bottom of the coil is assumed to be flowing *into* the coil referenced to the feedpoint current. EZNEC references all currents to the feedpoint current which (surprise!) is feeding, i.e. flowing into the antenna. If the current at the bottom of the coil is out of phase with the feedpoint current, by convention, the current is flowing in the opposite direction to the feedpoint current, i.e. out of the coil. What you say is irrelevant to the established conventions. What is a sophomoric notion is your notion that current doesn't flow when it's associated with a coil. I have no such notion. You can't have it both ways, Jim. Either current flows into a coil or it doesn't. I say it does for 1/2 cycle referenced to the source. You are arguing with me about that assertion. Then I observe that neither you nor Tom completely understands standing waves. I don't "completely understand" anything, Jim. It is delusional to believe that you are unique in completely understanding anything. May I remind you of something Einstein said: "One thing I have learned in a long life: that all our science, measured against reality, is primitive and childlike ..." The current in standing waves flows - it doesn't stand still. You have been seduced by your math model. Current can only stand if dQ/dt equals zero. Otherwise, it is flowing in one of two possible directions available in a wire. Your notion of current phase is literally a figment of your imaginary number imagination. All real-world non-zero current is real and, in a wire, flows in only one of two possible directions. By convention, that direction is the sign of the cosine term referenced to the source. The magnitude of the current is Imax*cos(x). The phase is always either zero or 180 degrees. There is absolutely no difference in 1a at 45 deg. and 0.707a at zero deg. The j0.707a doesn't exist in reality. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim Kelley wrote:
Cecil Moore wrote: Yep, and for the same power level, a higher impedance usually means a lower current and vice versa. But the impedance *at* such points does not affect the current *at* those points? Cause and effect, Jim. Hint: The impedance equals v/i and is completely virtual, i.e. clearly a result, not a cause. Even the feedpoint impedance of an antenna is a ratio of v/i which is often simply the result of interference between forward and reflected waves. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil Moore wrote: There exists current at the base of a coil. It either flows into the coil or away from the coil. If it is DC current, you're right. If it is AC, then you're talking about wave propagation. You're confusing the two things. You have to decide which one you want to talk about. Both in to and out of. Not one or the other. You are forgetting your conventions. If the current at the bottom of the coil is in phase with the feedpoint current, it is flowing the same direction as the feedpoint current. By convention, the feedpoint current is assumed to be flowing *into* the antenna. Therefore, by convention, the in-phase current at the bottom of the coil is assumed to be flowing *into* the coil referenced to the feedpoint current. EZNEC references all currents to the feedpoint current which (surprise!) is feeding, i.e. flowing into the antenna. If the current at the bottom of the coil is out of phase with the feedpoint current, by convention, the current is flowing in the opposite direction to the feedpoint current, i.e. out of the coil. What you say is irrelevant to the established conventions. Not at all. What I say is the way AC voltage and currents are summed. We don't talk about alternating current flowing in only one direction or another. That would be silly. It's something I've only seen you do. 73, Jim AC6XG |
Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: Yep, and for the same power level, a higher impedance usually means a lower current and vice versa. But the impedance *at* such points does not affect the current *at* those points? Cause and effect, Jim. Hint: The impedance equals v/i and is completely virtual, i.e. clearly a result, not a cause. Little v over little i, Cecil? Are we talking instantaneous impedances now also? ;-) 73, Jim AC6XG |
Jim Kelley wrote:
Cecil Moore wrote: At any instant of time at a standing wave current maximum point (loop, antinode), the charge carriers are either moving toward the load (ends of the dipole) or toward the source (feedpoint). You do understand that a standing wave pattern is NOT a plot of instantaneous voltages or currents, right? It is whatever you define it to be, Jim. You cannot display a real- time plot on a piece of paper. The standing wave patterns in The ARRL Antenna Book are RMS patterns. I have also seen them plotted as envelope patterns which is, IMO, a better representation. Whatever is plotted on a sheet of paper is some sort of time-frozen snapshot, by definition. EZNEC can display the relative phase of standing wave current, or not, depending upon what you want. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: At any instant of time at a standing wave current maximum point (loop, antinode), the charge carriers are either moving toward the load (ends of the dipole) or toward the source (feedpoint). You do understand that a standing wave pattern is NOT a plot of instantaneous voltages or currents, right? It is whatever you define it to be, Jim. If that's what you think, then the answer is you don't know what a standing wave pattern is, and there really is nothing further I can discuss with you on the subject. Good luck, and have fun in the contest OM. 73 de AC6XG |
Jim Kelley wrote:
Cecil Moore wrote: There exists current at the base of a coil. It either flows into the coil or away from the coil. If it is DC current, you're right. If it is AC, then you're talking about wave propagation. You're confusing the two things. You have to decide which one you want to talk about. Nope, it is you who are confusing waves (photons) with current (dQ/dt). I have said nothing about photon waves. Everything I have said applies to current, i.e. dQ/dt where the charge carriers are electrons and reverse direction every 1/2 cycle. That the electrons launch photons in waves is irrelevant to this current discussion. dQ/dt (current) doesn't change much because of photon acquisition or loss. We don't talk about alternating current flowing in only one direction or another. Of course we do, Jim. We talk about the AC generator source current flowing from the power stations to our houses. In general, AC current flowing in phase with the generator current is considered to be flowing away from the generator toward the load, by convention. This is clearly illustrated in my college textbooks where AC RMS values replace DC values. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim Kelley wrote:
Cecil Moore wrote: Cause and effect, Jim. Hint: The impedance equals v/i and is completely virtual, i.e. clearly a result, not a cause. Little v over little i, Cecil? Are we talking instantaneous impedances now also? ;-) Give me a break, Jim. I'm reading a book titled, "The Matter Myth", so my mind is blown and you are mostly empty space. :-) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim, as I read the arguement, (and these guys are RIGHT), you are confusing
current being constant, in a media, with POWER being constant in a media (minus insertion loss's, of corse). for example, visualize a 1/4 wave (or a 1/2 wave dipole) , at the feedpoint, what is the current? even at a 1:1 swr, in coax, the current is constant, as you predict! But, WHAT, PREY, is the current, at the far END (S) of that 1/4 wave (DIPOLE) ? answer is 0 ! but the voltage has increased to that necessary to equal the amount of power impressed on it (I realize that any number times, 0 = 0, but, obviously, there is a physical limit approaching this, and also, for the power to stay the same, you would have an INFINANT voltage!! This is the stuff that R.F. BURNS are made of! And, when SWR is measured in a cable, current (and voltage) will vary, depending upon WHERE , in the cable that you measure current, (or voltage, even tho, the POWER must stay the same, again considering losses in the transmission line: As information, another Jim, NN7K -- No trees were killed in the sending of this message. However, a large number of electrons were terribly inconvenienced "Jim Kelley" wrote in message ... Cecil Moore wrote: Jim Kelley wrote: Cecil Moore wrote: Yep, and for the same power level, a higher impedance usually means a lower current and vice versa. But the impedance *at* such points does not affect the current *at* those points? Cause and effect, Jim. Hint: The impedance equals v/i and is completely virtual, i.e. clearly a result, not a cause. Little v over little i, Cecil? Are we talking instantaneous impedances now also? ;-) 73, Jim AC6XG |
Jim, AC6XG wrote:
"But the impedance "at" such points does not affect the current "at" such points?" "At" is a perfectly good preposition. R-F current can`t properly be said to be "in" the wire due to skin effect. The point I invoked was that at a certain distance along an antenna or a transmission line, or at a certain distance from some reference point there are values which are functions of the location. Often the load is the reference chosen for a transmission line. Often the tip end of a standing-wave antenna is used as a reference for distributions along an antenna. When we know how many degrees a point lies back from the open end of an ordinary standing-wave antenna a point is, we can predict many characteristics of that point. Impedance is a function of position on an antenna or on a transmission line with reflections. Impedance is a voltage to current imposed on a point. On a standing-wave antenna, there are two significant actions which are related but separate which I want to mention. The first is a somewhat uniform, but declining due to radiation, incident power flow toward the open-circuit end of the antenna. The second is a somewhat uniform, but declining reflected power flow back from the open-circuit end of the antenna which travels back toward the generator of the power. Just as in a transmission line, were you to sense the power flowing each direction alone, via a directional coupler, no standing waves would be seen. It is only the superposition of the forward (incident) and reflected waves that produces the familiar display that we might sense with a slotted (trough) line. The value of standing waves is mainly as an indicator of mismatch. A transmission line has an iron-clad Zo due to its construction which imposes the same voltage to current ratio (Zo) on incident and reflected waves at every spot along the transmission line. Not so with the surge impedance (Zo) of the antenna wire. Zo of the antenna wire can be measured and calculated. It is a function of position along tjhe antenna. For some calculations an average Zo of an antenna is useful. I don`t remember everything from my studies over a half century ago. Even If I did, most readers would either drop off to sleep or find a more interesting activity. I have no intention of trying to teach a course in antennas and transmission lines. My impression is that Cecil is right on target in this thread. Best regards, Richard Harrison, KB5WZI |
Jim Kelley wrote:
We don't talk about alternating current flowing in only one direction or another. That would be silly. It's something I've only seen you do. How about a reference? _Alternating_Current_Circuits_, by Kerchner and Corcoran, 3rd edition, page 97. It is an AC circuit. There is an arrow labeled 'I' for the current. The arrow exists in only one direction. We know the current is not flowing in only one direction in an AC circuit but the 'I' arrow assigns a convention reference for direction of the AC current flow. In the accompanying diagram, that 'I' is assigned a value of I at zero deg. The source voltage is also an arrow labeled 'V' which points in only one direction. So whadda mean "we" white man? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Richard Harrison wrote: Jim, AC6XG wrote: "But the impedance "at" such points does not affect the current "at" such points?" "At" is a perfectly good preposition. R-F current can`t properly be said to be "in" the wire due to skin effect. I agree. Cecil doesn't. Perhaps you missed the post where he took issue with the term. FB on all the rest. We're on the same page. My impression is that Cecil is right on target in this thread. Even his notion of an alternating current standing wave having a net "direction" in which current flows? 73, Jim AC6XG |
Cecil Moore wrote: Jim Kelley wrote: We don't talk about alternating current flowing in only one direction or another. That would be silly. It's something I've only seen you do. How about a reference? _Alternating_Current_Circuits_, by Kerchner and Corcoran, 3rd edition, page 97. It is an AC circuit. There is an arrow labeled 'I' for the current. The arrow exists in only one direction. We know the current is not flowing in only one direction in an AC circuit but the 'I' arrow assigns a convention reference for direction of the AC current flow. In the accompanying diagram, that 'I' is assigned a value of I at zero deg. The source voltage is also an arrow labeled 'V' which points in only one direction. So whadda mean "we" white man? Ya gotta be kidding, Cecil. Do you really not know that the arrow simply indicates the direction of positive current flow? Yikes. 73, Jim AC6XG |
Jim Kelley wrote:
I agree. Cecil doesn't. Perhaps you missed the post where he took issue with the term. Looks like you missed that post, Jim. I have never taken issue with skin effect. Even his notion of an alternating current standing wave having a net "direction" in which current flows? Please stop misrepresenting what I posted, Jim. The AC current in standing waves possesses an instantaneous direction of current flow which reverses every 1/2 cycle (or 1/2 WL). I have made no assertions about waves, only about dQ/dt, which is current involving electron charge carriers. A positive dQ/dt is generally considered to be flowing toward the load. A negative dQ/dt is generally considered to be flowing toward the source. It's pretty sad to have to resort to misrepresentations to try to save face. You still don't seem to comprehend the difference between photons (waves) and electrons (charge carriers). Accelerated electrons launch photon waves but are themselves not much affected by that action. -- 73, Cecil, W5DXP |
Jim Kelley wrote:
Ya gotta be kidding, Cecil. Do you really not know that the arrow simply indicates the direction of positive current flow? You have been making fun of me for using such an arrow, Jim. Now it appears that you have cracked open a reference book and realize how wrong you were. This is what I have been saying all along. The arrow indicates the direction of current flow when I* cos(phase_angle) is positive. 1/2 cycle later, the current is flowing in the opposite direction, i.e. I*cos(phase_ angle) is negative. That's what you have been disagreeing with and ****ing and moaning about for about a week now. You said direction of current flow and cos(phase_angle) were unrelated. -- 73, Cecil, W5DXP |
Cecil Moore wrote: Jim Kelley wrote: Ya gotta be kidding, Cecil. Do you really not know that the arrow simply indicates the direction of positive current flow? The arrow indicates the direction of current flow when I* cos(phase_angle) is positive. 1/2 cycle later, the current is flowing in the opposite direction, i.e. I*cos(phase_ angle) is negative. The arrow does not indicate "the direction AC is flowing" - which is what you've been trying to imply. Moreover, it has nothing to do your claim that more alternating current flows into one end of an inductor than flows out of the other. As I have been saying all along, that particular notion is invalid. When the value I in the expression i = I*sin(w) for a standing wave happens to be greater at one end of a transmission line than the corresponding value of I at the other end of the transmission line, it is NOT true, or correct to say that more current is flowing into one end than is flowing out of the other. It's totally bogus electronics. I wish you would be courageous enough to stand corrected on that point. 73, Jim AC6XG |
Jim Kelley wrote:
The arrow does not indicate "the direction AC is flowing" - which is what you've been trying to imply. Sorry Jim, I never tried to imply anything of the sort. The arrow, which is just a convention, indicates the direction of instantaneous current flow when cos(phase_angle) is positive which is during 1/2 of the cycle. The instantaneous current flows in the opposite direction 1/2 cycle later when cos(phase_angle) is negative. You have argued loud and long that current phase has nothing to do with current direction. That's just simply false. In fact, the current phase and direction of current flow in the wire are 100% correlated. Moreover, it has nothing to do your claim that more alternating current flows into one end of an inductor than flows out of the other. As I have been saying all along, that particular notion is invalid. Tom's and Roy's own measurements proved that the measured current at the bottom of the coil is greater than the measured current at the top of the coil. Those currents are not standing still. They are flowing in and out of the coil and have been proven not to be equal by actual measurements. Let's look at one example again. The current at the bottom of the coil is 0.87 at -1.23 deg and the current at the top of the coil is 0.67 at -1.57 deg. (Those angles deviate from zero degrees by a negligible amount.) The cosines of those phase_angles are positive indicating that we are on the '+' side of the axis (in phase with the feedpoint current) so we draw the current arrow into the bottom of the coil and out the top of the coil. Your objection to that commonly accepted convention is noted. With the positive feedpoint current as our reference, we label the current arrow pointing into the bottom of the coil as 0.87 amps and we label the arrow pointing out of the top of the coil as 0.67 amps. So we have: Source Current at Current at Current Bottom of coil top of coil 1.0 amp 0.87 amp 0.67 amp --- ---- coil --- --------------------------------////////------------------------ At the time in the cycle when the instantaneous source current is positive, the current into the bottom of the coil is positive and greater than the current out of the top of the coil which is also positive. When the value I in the expression i = I*sin(w) for a standing wave happens to be greater at one end of a transmission line than the corresponding value of I at the other end of the transmission line, it is NOT true, or correct to say that more current is flowing into one end than is flowing out of the other. It's totally bogus electronics. I wish you would be courageous enough to stand corrected on that point. The net current is the phasor sum of the forward current and reflected current. It can indeed vary from one point in the transmission line to another and it does exactly that in a line with reflections. I said long ago that the forward current in a transmission line is relatively constant and the reflected current is relatively constant. But their phasor sum, the net current, can vary from zero to almost double the value of the forward current and anywhere in between including positive and negative values. By convention, if it is positive, it is flowing toward the load. If it is negative, it is flowing toward the source. Non-zero standing-wave current reverses its direction of flow every 1/2 cycle, i.e. it doesn't just stand still contrary to its name. With a single inductive pickup, you cannot tell a standing-wave current from a traveling-wave current. That fact speaks volumes. -- 73, Cecil, W5DXP |
Cecil Moore wrote:
You have argued loud and long that current phase has nothing to do with current direction. If that's what you think, then you misunderstood. Tom's and Roy's own measurements proved that the measured current at the bottom of the coil is greater than the measured current at the top of the coil. I note you using the term AT now. Very good. I agree with it. I also note that you no longer say the current into the bottom of the coil is greater than the current our of the top of the coil. That is what I objected to at the beginning of this mess. Those currents are not standing still. Never said current stands still, Cecil. You're the only one whose said anything about that. What I've said is that alternating current isn't unidirectional. They are flowing in and out of the coil and have been proven not to be equal by actual measurements. Exactly what I've been saying - repeatedly, all along. I'm glad you finally agree. 73, Jim AC6XG |
Cecil wrote, among other things, ... With a single inductive pickup, you cannot tell a standing-wave current from a traveling-wave current. That fact speaks volumes. -- 73, Cecil, W5DXP Maybe you can't, but I can. Actually, you can, too. Just move the probe a little bit, laterally, and observe the amplitude on the O'scope screen. If it changes, it's not a pure travelling wave. 73, Tom Donaly, KA6RUH |
Tdonaly wrote:
Maybe you can't, but I can. Actually, you can, too. Just move the probe a little bit, laterally, and observe the amplitude on the O'scope screen. Forgot to say, this is a hands off experiment. No moving allowed. One and only reading is taken at one point and only one point. Is that one reading standing wave current or forward current or reflected current? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim Kelley wrote:
Cecil Moore wrote: You have argued loud and long that current phase has nothing to do with current direction. If that's what you think, then you misunderstood. Would you like for me to re-post your posting where you said phase had nothing to do with direction? When you change your mind about something, it would be nice if you were man enough to admit it. Saying that you already knew everything that will ever be known is getting pretty old. I also note that you no longer say the current into the bottom of the coil is greater than the current our of the top of the coil. OK, I will repeat that the current into the bottom of the coil is greater than the current out of the top of the coil (during the 1/2 cycle when they are both positive). The words in parentheses are always implied by convention when talking about something like this but you already knew that. Please don't tell me that the hard time you have been giving me was over an implied semantic context that everyone already understands is a standard accepted convention. Those currents are not standing still. Never said current stands still, Cecil. Would you like for me to re-post your posting that says the standing wave current doesn't move and never enters the coil? You said because that was true, I didn't understand standing waves. They are flowing in and out of the coil and have been proven not to be equal by actual measurements. Exactly what I've been saying ... Now everyone can see that you are just flat out lying. You insisted that standing wave current does not flow into a coil and argued with me when I said it did. Hint for you, Jim: The current cannot flow in and out without first flowing in, which you asserted doesn't happen. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
On Thu, 19 Feb 2004 18:13:02 -0600, Cecil Moore
wrote: Tdonaly wrote: Maybe you can't, but I can. Actually, you can, too. Just move the probe a little bit, laterally, and observe the amplitude on the O'scope screen. Forgot to say, this is a hands off experiment. you mis-spelled waving. SWR = Standard hands Waving Ridiculousness |
Cecil,
Let me show you what I mean about being specific when comparing antennas. You spoke of a "simple" dipole that was not rotatable that had a high gain per Eznec The dipole I believe was for 10 metres with a lobe gain in the order of 10 db, you didn't say what the minimum gain was which is crucial when comparing antennas So I just designed an antenna with a computor program for 160 metres based around a patent write up of mine which probably will not be issued until sometime next year. The beam is rotatable and is at a height of 20 metres. The max gain is 7.35 dbi at 87degrees. Minimum gain at this TOA is a few db less. Compared to another antenna, and that is what you are doing, the gain exceeds a Beverage at any angle over 10 degrees even if the beverage was rotatable. Unlike the Beverage the antenna can be used for transmitting. Now my antenna in the backyard has slightly different dimensions because the material used was available so the gain is down somewhat and ofcourse the ground is not perfect. So Cecil, that is what I mean about supplying relevant data tho perhaps it would be better if I described the antenna as a very SHORT dipole. Cecil you now have a SPECIFIC antenna that can be used for comparison purposes based on keyboard design that is horizontally polarised Cheers Art Unwin KB9MZ PS Nothing wrong with the browser I am just abstaining for a while because of work time limits at this time. "Cecil Moore" wrote in message ... Art Unwin KB9MZ wrote: Cecil we have severe weather here that it requires a real snow job from me to emerge back into this particular thread !!!!! Just remember when Einstein said, "God doesn't roll dice", one of the QED physicists replied that, "Not only does God roll dice, he rolls them in the dark." :-) What's wrong with your browser? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Cecil Moore wrote: Saying that you already knew everything that will ever be known is getting pretty old. :-) I think that's your trick, Cecil. Funny how when you get backed into a corner you start doing a lot of projecting - projecting your very distinctive personality flaws onto others. Please don't tell me that the hard time you have been giving me was over an implied semantic context that everyone already understands is a standard accepted convention. You started an enormous argument with a whole group of people on this newsgroup because of your alleged "accepted convention". Had you not worded the idea of a current taper in the way you did, you could have avoided much of it. Since I've supported Yuri's claim from the very beginning, my only point to all of this was to try to peruade you to put forward the most cogent argument. Obviously, you care for little other than the arguing part of it. More alternating current does NOT go into one end of ANY series component than comes out the other. It's a completely stupid idea no matter how many words you use to try to get around it. It's just bloody wrong. Those currents are not standing still. Never said current stands still, Cecil. Would you like for me to re-post your posting that says the standing wave current doesn't move and never enters the coil? Would you like for me to try to explain to you again what the words I used mean? Evidently I need to. Perhaps then you would be able to recite them more accurately. They are flowing in and out of the coil and have been proven not to be equal by actual measurements. Exactly what I've been saying ... Now everyone can see that you are just flat out lying. I used exactly those words in a previous post, Cecil. You apparently have a pretty low opinion of 'everyone' if you think they're that gullable. Although it does seem Steve fell for it hook, line, and sinker. I guess my congrats would be in order for that. You insisted that standing wave current does not flow into a coil and argued with me when Nope. I'm on record here as having observed simply that standing waves stand, hence the name. The 'wave' does not move. As most others here were probably able to ascertain, I was illustrating the simple fact that the graph you refer to is a standing wave plot. A standing wave plot shows current amplitude as a function of postion. It doesn't show current moving in some direction - i.e. into the bottom or out of the top of something. Unless you're talking about wave propagation, there's no utility in that notion - particularly since any useful information about the waveforms is conveyed in the wave function equation. I said it did. Hint for you, Jim: The current cannot flow in and out without first flowing in, which you asserted doesn't happen. :-) Is there no limit to how asinine you allow yourself to be? 73, Jim AC6XG |
Art, did you intend to compare a 'CLOUD WARMER' against an 'OVER THE
HORIZON' class of antenna? Isn't that apples and oranges? BTW, who limits Beverages to received ONLY? There are some very long Beverages in VK land for long haul low band DX. DD, W1MCE aunwin wrote: SNIP So I just designed an antenna with a computor program for 160 metres based around a patent write up of mine which probably will not be issued until sometime next year. The beam is rotatable and is at a height of 20 metres. The max gain is 7.35 dbi at 87degrees. Minimum gain at this TOA is a few db less. Compared to another antenna, and that is what you are doing, the gain exceeds a Beverage at any angle over 10 degrees even if the beverage was rotatable. Unlike the Beverage the antenna can be used for transmitting. SNIP |
aunwin wrote:
So Cecil, that is what I mean about supplying relevant data ... Well, in a nutshell, I route my dipole such that the four 11 dBi lobes on 10m are aimed at the English speaking land masses of the world. That works like a charm (for me). If I ever have trouble reading someone, I switch over to my rotatable dipole with only a 9 dBi gain and TOA of 10 deg to see if the QSO can be improved. I seriously doubt that any vertical monopole can beat my rotatable dipole with 9dBi gain and TOA of 10 degrees. I also doubt that any two element vertical phased array can beat 9 dBi at 10 deg TOA. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim Kelley wrote:
More alternating current does NOT go into one end of ANY series component than comes out the other. It's a completely stupid idea no matter how many words you use to try to get around it. It's just bloody wrong. BS, Jim. It happens all the time in distributed networks, especially in transmission lines with reflections. You are so hung up on lumped circuit theory that you have forgotten there ever was such a thing as distributed network analysis. I notice you have deleted everything in my postings that proves you wrong. One wonders why. Hint for you, Jim: The current varies from point to point all up and down a transmission line with reflections. Saying that the current doesn't vary in a transmission line with reflections is absolutely ridiculous. The AC current at a current node may be zero. The AC current at a current loop may be 100 amps. Jim, by any stretch of the imagination, zero amps is NOT equal to 100 amps. For instance, for an open-circuited 1/4WL stub, the current flowing into the stub is very high. The current at the open end is zero. How you can assert that they are equal is beyond belief. Nope. I'm on record here as having observed simply that standing waves stand, hence the name. The 'wave' does not move. But the subject isn't waves, it is current. Standing wave current CANNOT stand still. Within the standing wave, the current is flowing in the opposite direction every 1/2 cycle. Why is that so difficult for you to comprehend? Is there no limit to how asinine you allow yourself to be? If quoting your ridiculous assertions makes me asinine, then so be it. How you can assert that there is a current taper in a coil, yet argue that the current cannot be different at each end of the coil is pathological. If the current cannot be different, where does the current taper come from? -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Richard Clark wrote:
And "somehow?" This adverb presumes odds for which there were never any chance to offer odds for in the first place. At least such statements are consistent with the topic (you keeping notes Steve?). The word, "somehow", in that context, Richard, is reserved for two-year olds and r.r.a.a readers with the comprehension level of a two-year old. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
"Dave Shrader" wrote in message news:%huZb.24701$Xp.104370@attbi_s54... Art, did you intend to compare a 'CLOUD WARMER' against an 'OVER THE HORIZON' class of antenna? Isn't that apples and oranges? No it is not, both have gain.It is just that the maximum gain is at different angles both vertically and horizontally.Extra gain in an undesired direction is just plain useless. There is absolutely no reason why a rotatable antenna cannot beat a standard beverage depending where your interest are. If your interests are ambiguos then so will be your comparison responses , something I am sure you understand. BTW, who limits Beverages to received ONLY? There are some very long Beverages in VK land for long haul low band DX. I will give you that but in general they are used for listening but that was not the message I was trying to supply, Cecil supplied simple dipole gain as stated by EZNEC so I had the computor supply a 'better' antenna but what does it really mean. Suppliers of computor programs state if it does not look real then it is not! So the simple statement of gain is meaningless if it is directed at not acceptable areas which is why I pointed to ambiguety. Now for my actual antenna which is rotatable on 160, what is the gain at 90 degrees which you label as NVIS would be acceptable if the computor supplied it to you ? If given the the gain at 90 degrees would you interpret that as having zero over the horizon at say 15 degrees ?. Zero at 30 degrees? I would say that if an antenna is a cloud warmer it does not necessarily discriminate against low angle signals so it is not or should not be a statement of derisement. Frankly this business of comparing antennas is pretty stupid UNLESS one prescribes a specific object . Cecil gave such a comparison but did not reveal that in many directions his antenna was just plain deaf. Good for confusion or for an ensuing augument but other than that it had no value. I would also add that if a computor gives you a surprising figure then you must have a second opinion or make one. To do anything else is to admit all is known and figures of merit are known for every shape and size and are printed in books so one can learn what is not real when shown on a monitor. Were you not ever surprised during your years on the range at what your equipment revealed? Did you ever compare antennas where one had more gain than the other but proved to be actually deaf in some directions ? I am quite sure that during your working career any statements you made with regard to antennas was specific and to the point and devoid of vague statements which were not pertinent to the assignment given. If it wasn't then your career was short. Nothing personal intended above I was just trying to make a point with Cecil to whom I addressed the posting but I welcome your remarks. Regards Art .. aunwin wrote: SNIP So I just designed an antenna with a computor program for 160 metres based around a patent write up of mine which probably will not be issued until sometime next year. The beam is rotatable and is at a height of 20 metres. The max gain is 7.35 dbi at 87degrees. Minimum gain at this TOA is a few db less. Compared to another antenna, and that is what you are doing, the gain exceeds a Beverage at any angle over 10 degrees even if the beverage was rotatable. Unlike the Beverage the antenna can be used for transmitting. SNIP |
"Cecil Moore" wrote in message ... aunwin wrote: So Cecil, that is what I mean about supplying relevant data ... Well, in a nutshell, I route my dipole such that the four 11 dBi lobes on 10m are aimed at the English speaking land masses of the world. That works like a charm (for me). If I ever have trouble reading someone, I switch over Cecil now you have decided to add to your original statement regarding comparisons and whoa you switch over to other means of communication when this antenna lets you down so badly , so having a back up like a phone makes the antenna worthwhile as a comparison with other antennas and you are admitting your previous info was misleading at best. to my rotatable dipole with only a 9 dBi gain and TOA of 10 deg to see if the QSO can be improved. I seriously doubt that any vertical monopole can beat my rotatable dipole with 9dBi gain and TOA of 10 degrees. I also doubt that any two element vertical phased array can beat 9 dBi at 10 deg Now you are at it again, you didn't mention anything about the length of your "simple dipole and yet you doubt that any two element ( why two elements) can beat 9 dbi at 10 degrees. You are suddenly believing your own misleading words, since you play games with the lengths in a simple diameter others can play the same silly game, two vertical elements surely can beat your antenna if they follow your rules,an element or dipole description in no way places a restriction on length. So your response is not just a nutshell as you stated, you are just playing nuts. But you are not alone inthis comparison game,somebody stated he read somewhere that the dipole was such and such efficient which is absolutely silly if that is all you remember since you have to know efficiency over what! Surely he could have introduced some thoughts of his own like compared to a broom stick but no, suffice enough that he read that little bit in a book! Again nothing personal but I agree with Mark these discussions are not worthy of you when ambiguety is deliberately inserted purely to win a debate rather than advance the cause of science. Cecil you are smart enough to discuss most things on its merits, why stoop to the level of some who prefer to supply monologues onEHantennas or something else to prove theycan fill a page with garbage and trick others to read it ? Best regards and I do mean it as this is not meant to be a personal attack Art TOA. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
aunwin wrote:
Cecil you are smart enough to discuss most things on its merits, ... Well, in a nutshell, Art, a vertical has to overcome an s7 noise level at my QTH to hear anything. The dipole only has to overcome an s4 noise level. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Jim Kelley wrote:
Cecil Moore wrote: Jim Kelley wrote: You do understand that a standing wave pattern is NOT a plot of instantaneous voltages or currents, right? It is whatever you define it to be, Jim. If that's what you think, then the answer is you don't know what a standing wave pattern is, and there really is nothing further I can discuss with you on the subject. I know what a standing wave pattern is, Jim, and it is nothing that can be put on a sheet of paper. It is a dynamically changing pattern. Anything on paper is just a freeze-frame snapshot. I am surprised that you don't know that. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Tdonaly wrote:
What's that you said about ad hominem attacks, Cecil? The last part of "ad hominem" means "to the man", Tom, not to the Flat Earth *Society*. An ad hominem attack, by definition, is aimed at an individual, not at a group. If you have to sink to misrepresenting other people's ideas in order to "win" your argument, you've actually admitted that you've lost. I treat people the way I am first treated by them, Tom. If one wants me to treat him like a decent human being, then one has to act decently. There are a number of people on this newsgroup who act decently and a number who don't. I notice that instead of just admitting that a real-world physically large loading coil can occupy 1/2 wavelength, you are having to resort to accusations of ad hominem attacks as a diversion away from that central issue. Falsely accusing me of an ad hominem attack when I rag on the Flat Earth Society *is* an ad hominem attack so "you've actually admitted that you've lost." Your words, copied and pasted from above. Hint: Be civil to me and I'll be civil to you. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
a veritable font of flat earth socialist semantic nonsense:
On Sat, 21 Feb 2004 10:52:43 -0600, Cecil Moore wrote: Falsely accusing me of an ad hominem attack when I rag on the Flat Earth Society *is* an ad hominem attack so "you've actually admitted that you've lost." On Tue, 17 Feb 2004 17:07:41 -0600, Cecil Moore wrote: It's not ad hominem if it's true |
Richard Clark wrote:
a veritable font of flat earth socialist semantic nonsense: In accordance with the subject of this thread. But it's libertarian, not socialist. :-) -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
Richard Clark wrote: a veritable font of flat earth socialist semantic nonsense: What does the "socialist" crap have to do here? Another twisted tangent of smokey mirrors to obscure the reality? IMWTK Yuri |
Cecil, W5DXP wrote:
"Anything on paper is just a freeze-frame snapshot." Yes, as a-c alternates, standing-waves stand. Standing-wave ratio=SWR SWR = Emax/Emin, or SWR = Imax / Imin. The ratio is the same for volts or amps. SWR expresses the magnitude of the reflection coefficient. Reflection coefficient= Rho Rho=(ZL/Zo)-1 / (ZL/Zo)+1 There are no volts or amps in the expression for Rho, so it is independent of signal strength. Though we may find SWR with a voltage probe, SWR is only indicating severity of mismatch which is a function of impedance ratios and is independent volts, amps, and power. So long as you are consistent in using rms, peak, or even instantaneous values at the same point in the cycle of voltage or current, SWR values can be good. A good SWR meter reading does not depend on signal strength. Best regards, Richard Harrison, KB5WZI |
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"aunwin" wrote in message
If given the the gain at 90 degrees would you interpret that as having zero over the horizon at say 15 degrees ?. Zero at 30 degrees? I would say that if an antenna is a cloud warmer it does not necessarily discriminate against low angle signals so it is not or should not be a statement of derisement. It's simple to check using eznec. One advantage eznec has over some other programs as far as the plot... You do a far field plot, and look at the pattern plot. You will see max gain at a certain angle. At that angle , at the top of the plot, you will see a little green ball. You can "grab" that green ball or marker and drag it down to whatever angle you want to look at. You could check overhead, at 20 degrees, 10, 5, or whatever angle you want to see. Frankly this business of comparing antennas is pretty stupid UNLESS one prescribes a specific object . That ain't no joke... MK |
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