|
ART vs. W8JI
Arrt,
I have repeatedly asked you to supply us with your original quote from W8JI's page concerning a straight radiator is the best. Will you please do so? Now, there's an entire thread on this and no where any foundation. Dale W4OP |
ART vs. W8JI
On Sep 2, 2:01*pm, "Dale Parfitt" wrote:
Arrt, I have repeatedly asked you to supply us with your original quote from W8JI's page concerning a straight radiator is the best. Will you please do so? Now, there's an entire thread on this and no where any foundation. Dale W4OP And no real discussion here either! You did not contribute Dale, you can cry and cry and moan as much as you want. I will not let you bully me and I am not at your beck and call. If you have a comment with respect to the advantages of a radiater being straight or not then go ahead and speak .If you feel hurt send an E mail to Tom. Failing that go to QRZ yourself where I told you to go. Sooner or later you will have to get up from your couch |
ART vs. W8JI
Dale,
You should know better than that. Asking Art to prove something? You gotta be kidding. - 'Doc |
ART vs. W8JI
On Sep 2, 6:24*pm, "'Doc" wrote:
Dale, You should know better than that. *Asking Art to prove something? *You gotta be kidding. *- 'Doc And why not? This is a discussion group. Any one can concur or challenge the statement. If I supply the proof of anything then silly attacks begin I can handle them but it does not improve on my knoweledge. I will state right now that overall size or straightness of a radiator is not implied in Maxwell's laws in any way. So I would like to know where that notion came from. Is that so bad? So Doctor, what have you got to offer regarding radiator straightness as a person skilled in the art ? |
ART vs. W8JI
On Sep 2, 7:54*pm, Art Unwin wrote:
On Sep 2, 6:24*pm, "'Doc" wrote: Dale, You should know better than that. *Asking Art to prove something? *You gotta be kidding. *- 'Doc And why not? This is a discussion group. Any one can concur or challenge the statement. If I supply the proof of anything then silly attacks begin I can handle them but it does not improve on my knoweledge. I will state right now that overall size or straightness of a radiator is not implied in Maxwell's laws in any way. So I would like to know where that notion came from. Is that so bad? So Doctor, what have you got to offer regarding radiator straightness as a person skilled in the art ? Art, you already conceded to an exercise in futility that was a very good example of a bent antenna in its worst case. You would think you would have learned your lesson. Jimmie |
ART vs. W8JI
Dale Parfitt wrote:
I have repeatedly asked you to supply us with your original quote from W8JI's page concerning a straight radiator is the best. Quoting W8JI's web page: "How do we make a small antenna as efficient as possible?" "... we make the antenna as large and straight as possible in a line. We don't fold, bend, zigzag, or curve the antenna especially in the high current areas." I don't know what the fuss is all about. Transmission line currents don't radiate (much) because they are out of phase. Random folding of an antenna more often than not introduces transmission line currents into the antenna itself - not good for radiation purposes. Transmission line currents cause destructive interference - that's good for transferring power from one place to another but not good for radiating RF. There are certain special-case antennas where folding occurs without introducing destructive interference, e.g. a 1/2WL folded dipole or a full-wave quad where the wires are a large enough percentage of a wavelength apart so they don't cause near-field destructive interference. Hint: RF radiation cannot be understood without understanding constructive and destructive interference in the near, medium, and far fields. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
Cecil Moore wrote:
There are certain special-case antennas where folding occurs without introducing destructive interference, e.g. a 1/2WL folded dipole or a full-wave quad where the wires are a Cecil, you should know by now that a half wave dipole of any type couldn't be all that efficient or effective. Art says so. tom K0TAR |
ART vs. W8JI
"Cecil Moore" wrote in message ... Dale Parfitt wrote: I have repeatedly asked you to supply us with your original quote from W8JI's page concerning a straight radiator is the best. Quoting W8JI's web page: "How do we make a small antenna as efficient as possible?" "... we make the antenna as large and straight as possible in a line. We don't fold, bend, zigzag, or curve the antenna especially in the high current areas." I don't know what the fuss is all about. Transmission line currents don't radiate (much) because they are out of phase. Random folding of an antenna more often than not introduces transmission line currents into the antenna itself - not good for radiation purposes. Transmission line currents cause destructive interference - that's good for transferring power from one place to another but not good for radiating RF. There are certain special-case antennas where folding occurs without introducing destructive interference, e.g. a 1/2WL folded dipole or a full-wave quad where the wires are a large enough percentage of a wavelength apart so they don't cause near-field destructive interference. Hint: RF radiation cannot be understood without understanding constructive and destructive interference in the near, medium, and far fields. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com Thank you Cecil, That's all I was looking for. Dale W4OP |
ART vs. W8JI
On Sep 2, 7:34*pm, Cecil Moore wrote:
Dale Parfitt wrote: I have repeatedly asked you to supply us with your original quote from W8JI's page concerning a straight radiator is the best. Quoting W8JI's web page: "How do we make a small antenna as efficient as possible?" "... we make the antenna as large and straight as possible in a line. We don't fold, bend, zigzag, or curve the antenna especially in the high current areas." I don't know what the fuss is all about. Transmission line currents don't radiate (much) because they are out of phase. Random folding of an antenna more often than not introduces transmission line currents into the antenna itself - not good for radiation purposes. Transmission line currents cause destructive interference - that's good for transferring power from one place to another but not good for radiating RF. There are certain special-case antennas where folding occurs without introducing destructive interference, e.g. a 1/2WL folded dipole or a full-wave quad where the wires are a large enough percentage of a wavelength apart so they don't cause near-field destructive interference. Cecil It is not related to volume. It is because they are both closed circuits thus all radiation can be accounted for i.e. all the circuit wire contribute to radiation. Any length less than 1WL does not ! If one introduces lumped loads then you have to cancel them, no problem. Maxwell clearly stated that we are dealing with distributed loads only, ie root L.C. The inclusion of volume is only because some people cling to the magnetic field theory as opposed to the particle theory. Equilibrium allows for multiple shapes and sizes for achievement Regards Art Hint: RF radiation cannot be understood without understanding constructive and destructive interference in the near, medium, and far fields. -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com |
ART vs. W8JI
tom wrote:
Cecil, you should know by now that a half wave dipole of any type couldn't be all that efficient or effective. Art says so. Art might be quick to point out that there is one wavelength of wire in a 1/2WL folded dipole. :-) -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
Art might be quick to point out that there is one
wavelength of wire in a 1/2WL folded dipole. :-) _______________- But does Art realize that a 1/2-wave dipole is a fractional wavelength radiator that couldn't possibly have his definition of "equilibrium," yet it has the same measured pattern and gain as a 1/2-wave folded dipole? RF |
ART vs. W8JI
On Sep 3, 9:13*am, Richard Fry wrote:
Art might be quick to point out that there is one wavelength of wire in a 1/2WL folded dipole. :-) _______________- But does Art realize that a 1/2-wave dipole is a fractional wavelength radiator that couldn't possibly have his definition of "equilibrium," yet it has the same measured pattern and gain as a 1/2-wave folded dipole? RF Yes, that is correct, but the power used on a 1/2 wave dipole is half that of a full wave. A closely folded dipole radiates the same as a Quad . View Cebik's comments on this |
ART vs. W8JI
On Sep 3, 10:26*am, Art Unwin wrote:
Yes, that is correct, but the power used on a 1/2 wave dipole is half that of a full wave. A full wave what? Are you calling a folded 1/2-wave dipole a full- wave antenna? For equal, matched power applied either to a 1/2-wave dipole or to a folded 1/2-wave dipole, and although their feedpoint currents will be different, both configurations will generate the same values of field intensity. Also how do you explain this, given that the 1/2-wave dipole by your definition does not have "equilibrium?" RF |
ART vs. W8JI
Dale Parfitt wrote:
Thank you Cecil, That's all I was looking for. You're welcome and I agree with 95% of what W8JI says. (For instance, he is mistaken about the delay through a 100T, 10TPI, 2" diameter 75m loading coil.) Some may or may not understand why random folding of antenna radiators tends to change the radiating conductors into non-radiating conductors. (The same effect is at work in loading coils.) When two conductors are carrying differential coherent currents with no common-mode current, there is negligible radiation when the two conductors are parallel to each other and the spacing is a very small fraction of a wavelength. It's called a transmission line and most of the losses at HF are I^2*R. Usually, one of the goals of a transmission line is not to radiate. Transmission line fields tend to cancel in the near field due to destructive interference. A single straight wire in free space is a very efficient radiator because interference occurs mostly in the far field. Fold it back upon itself and unless the second conductor is positioned perfectly, there will exist differential currents between the two conductors which will tend to cancel the radiation - leaving mostly I^2*R losses at HF. Small folded/loaded antennas tend to cancel the radiating fields. The only other avenue for a lot of the energy is conversion to heat. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
On Sep 3, 10:26*am, Art Unwin wrote:
Yes, that is correct, but the power used on a 1/2 wave dipole is half that of a full wave. On the chance that you meant a full-wave dipole in your quote above, I did a quick comparison of one with a 1/2-wave dipole (linked below). The peak, intrinsic gain of the full-wave is about 1.6 dB greater than the 1/2-wave -- which is due to the narrower lobe it produces. This has nothing to do with "equilibrium." The 2,082 -j583 ohm input Z of the full-wave version is not user friendly. But if zero-loss matching networks are used at the feedpoint of both antennas, then for EQUAL applied power to each, the peak field intensity produced by the full-wave dipole would be about 1.6 dB (20%) greater than from the 1/2-wave version. If the power applied to the full wave dipole was 1.6 dB less than applied to the 1/2-wave dipole, then their measured peak fields would be identical. But that is not a power reduction of one half (3 dB), as in your statement, Art. http://i62.photobucket.com/albums/h8...CompareArt.jpg RF |
ART vs. W8JI
Cecil Moore wrote:
Dale Parfitt wrote: Thank you Cecil, That's all I was looking for. You're welcome and I agree with 95% of what W8JI says. (For instance, he is mistaken about the delay through a 100T, 10TPI, 2" diameter 75m loading coil.) Some may or may not understand why random folding of antenna radiators tends to change the radiating conductors into non-radiating conductors. (The same effect is at work in loading coils.) Any relation to the loosely wrapped "coils" of shortened verticals like bug catchers? - 73 de Mike N3LI - |
ART vs. W8JI
Richard Fry wrote:
If the power applied to the full wave dipole was 1.6 dB less than applied to the 1/2-wave dipole, then their measured peak fields would be identical. But that is not a power reduction of one half (3 dB), Increase the length of the one wavelength dipole to a 1.25WL EDZ and the maximum gain indeed does increase by ~3dB over a 1/2WL dipole. Consider that the highest gain for a single-wire antenna with a figure-8 radiation pattern occurs with a feedpoint impedance of ~175-j1000 ohms, i.e. the antenna wire, by itself, is *non-resonant*. A parasitic element 1.25WL long would have a negligible effect on an antenna system. :-0 Consider that if one disconnects the feedline from a 1/2WL center-fed dipole, the two remaining 1/4WL wires separated by an insulator are *non-resonant*. Breaking guy wires into 1/4WL separated by insulators is one way of avoiding resonance. :-) -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
Michael Coslo wrote:
Any relation to the loosely wrapped "coils" of shortened verticals like bug catchers? Take a look at the geometry. Assuming that the current on one side of a turn on the coil is equal to the current on the opposite side of the coil but traveling in the opposite direction, one can see why those two currents per turn resemble transmission line currents (differential) rather than antenna currents (common- mode). (A 10" coil wound with 1/2WL of wire radiates roughly the same amount of energy as a 10" straight wire.) Physically large air-core loading coils can be modeled as a transmission line with a Z0 and VF (delay). http://hamwaves.com/antennas/inductance.html The delay through the coil can be calculated by knowing the Beta = _____ rad/m "Axial propagation factor of n=0 sheath helix waveguide mode at the design frequency" The VF of W8JI's 100T, 10TPI, 2" dia test coil calculates out to be ~0.03 resulting in a ~25 nS (~37 deg) delay through the coil at 4 MHz. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
Cecil Moore wrote:
Michael Coslo wrote: Any relation to the loosely wrapped "coils" of shortened verticals like bug catchers? Ack! I meant to write Hamsticks, not bug catchers! Sum daze I am in a daze! - 73 de Mike N3LI - |
ART vs. W8JI
On Sep 4, 7:04*am, Cecil Moore wrote:
Dale Parfitt wrote: Thank you Cecil, That's all I was looking for. You're welcome and I agree with 95% of what W8JI says. (For instance, he is mistaken about the delay through a 100T, 10TPI, 2" diameter 75m loading coil.) Some may or may not understand why random folding of antenna radiators tends to change the radiating conductors into non-radiating conductors. (The same effect is at work in loading coils.) When two conductors are carrying differential coherent currents with no common-mode current, there is negligible radiation when the two conductors are parallel to each other and the spacing is a very small fraction of a wavelength. It's called a transmission line and most of the losses at HF are I^2*R. Usually, one of the goals of a transmission line is not to radiate. Transmission line fields tend to cancel in the near field due to destructive interference. A single straight wire in free space is a very efficient radiator because interference occurs mostly in the far field. Fold it back upon itself and unless the second conductor is positioned perfectly, there will exist differential currents between the two conductors which will tend to cancel the radiation - leaving mostly I^2*R losses at HF. Small folded/loaded antennas tend to cancel the radiating fields. The only other avenue for a lot of the energy is conversion to heat. -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com Cecil I must respectively disagree. Your arguement is based on the presence of common mode current. When there is a state of equilibrium there is no vector that represents common mode. Since the radiator is a full WL that represents a period it is of closed circuit form. In such a case any radiator bend is accompanied by a bend that is equal and opposite per Newtons laws. The moment you introduce common mode currents you have strayed from the concepts of equilibrium, where all forces are accounted for. Maxwells laws are based on the position that all forces involved are accounted for where the summation of such equals zero. Regards |
ART vs. W8JI
On Sep 4, 8:54*am, Cecil Moore wrote:
Richard Fry wrote: If the power applied to the full wave dipole was 1.6 dB less than applied to the 1/2-wave dipole, then their measured peak fields would be identical. *But that is not a power reduction of one half (3 dB), Increase the length of the one wavelength dipole to a 1.25WL EDZ and the maximum gain indeed does increase by ~3dB over a 1/2WL dipole. Consider that the highest gain for a single-wire antenna with a figure-8 radiation pattern occurs with a feedpoint impedance of ~175-j1000 ohms, i.e. the antenna wire, by itself, is *non-resonant*. A parasitic element 1.25WL long would have a negligible effect on an antenna system. :-0 Consider that if one disconnects the feedline from a 1/2WL center-fed dipole, the two remaining 1/4WL wires separated by an insulator are *non-resonant*. Breaking guy wires into 1/4WL separated by insulators is one way of avoiding resonance. :-) -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com Cecil you misunderstood what I was saying . When you use a fractional WL then some of the wire cannot radiate, thus the impedance is reduced from that of a full WL. Power is still I sqd R Cos phi. where there is a varience. with the R in this case of a approx 1/2. Gain is not involved, only energy dissipated. Regards |
ART vs. W8JI
On Sep 4, 7:23*am, Richard Fry wrote:
On Sep 3, 10:26*am, Art Unwin wrote: Yes, that is correct, but the power used on a 1/2 wave dipole is half that of a full wave. On the chance that you meant a full-wave dipole in your quote above, I did a quick comparison of one with a 1/2-wave dipole (linked below). The peak, intrinsic gain of the full-wave is about 1.6 dB greater than the 1/2-wave -- which is due to the narrower lobe it produces. *This has nothing to do with "equilibrium." The 2,082 -j583 ohm input Z of the full-wave version is not user friendly. *But if zero-loss matching networks are used at the feedpoint of both antennas, then for EQUAL applied power to each, the peak field intensity produced by the full-wave dipole would be about 1.6 dB (20%) greater than from the 1/2-wave version. If the power applied to the full wave dipole was 1.6 dB less than applied to the 1/2-wave dipole, then their measured peak fields would be identical. *But that is not a power reduction of one half (3 dB), as in your statement, Art. http://i62.photobucket.com/albums/h8...CompareArt.jpg RF Gain has nothing to do with energy expended from a radiator. A folded dipole is of a full WL with an overall dimension of 1/2 WL. |
ART vs. W8JI
Art Unwin wrote:
Since the radiator is a full WL that represents a period it is of closed circuit form. My comments were about a one-wavelength straight wire dipole in free space. The reflections from the ends are what result in that large resonant resistance at the center. --Vf Open --If ----------------------fp---------------------- Circuit Vr-- Ir-- Zfp - feedpoint impedance, Vf - forward voltage, Vr - reflected voltage, If - forward current, Ir - reflected current Zfp = (Vf+Vr)/(If-Ir) = thousands of ohms However, if we fold the 1WL dipole into a circular 1WL loop it is still a standing-wave antenna but the phase of the reflections is reversed. Zfp = (Vf-Vr)/(If+Ir) = ~100 ohms. Where are those reflections coming from in a circular 1 WL loop? Why is the phase of the reflections reversed? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
On Sep 4, 12:53*pm, Cecil Moore wrote:
Art Unwin wrote: Since the radiator is a full WL that represents a period it is of closed circuit form. My comments were about a one-wavelength straight wire dipole in free space. The reflections from the ends are what result in that large resonant resistance at the center. * * * * * * * * * --Vf Open * * * * * * --If ----------------------fp---------------------- Circuit * * * * *Vr-- * * * * * * * * * Ir-- Zfp - feedpoint impedance, Vf - forward voltage, Vr - reflected voltage, If - forward current, Ir - reflected current Zfp = (Vf+Vr)/(If-Ir) = thousands of ohms However, if we fold the 1WL dipole into a circular 1WL loop it is still a standing-wave antenna but the phase of the reflections is reversed. Zfp = (Vf-Vr)/(If+Ir) = ~100 ohms. Where are those reflections coming from in a circular 1 WL loop? Why is the phase of the reflections reversed? -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com Equilibrium means equilibrium thus there are no reflections. Actions have an equal and opposite reaction. What are you going to draw upon for an equalizing vector? |
ART vs. W8JI
On Sep 4, 12:39*pm, Art Unwin wrote:
Gain has nothing to do with energy expended from a radiator. A folded dipole is of a full WL with an overall dimension of 1/2 WL. And for equal, matched power applied to their feedpoints, the total of the energy "expended" (radiated) by both them is identical. // |
ART vs. W8JI
Art Unwin wrote:
Equilibrium means equilibrium thus there are no reflections. No reflections on a standing-wave antenna? Where do the standing waves come from? -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
On Sep 4, 3:00*pm, Cecil Moore wrote:
Art Unwin wrote: Equilibrium means equilibrium thus there are no reflections. No reflections on a standing-wave antenna? Where do the standing waves come from? -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com There are no standing waves either |
ART vs. W8JI
On Sep 4, 3:40*pm, Art Unwin wrote:
On Sep 4, 3:00*pm, Cecil Moore wrote: Art Unwin wrote: Equilibrium means equilibrium thus there are no reflections. No reflections on a standing-wave antenna? Where do the standing waves come from? -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com There are no standing waves either Remember my WL is a closed circuit |
ART vs. W8JI
On Sep 4, 1:25*pm, Richard Fry wrote:
And for equal, matched power applied to their feedpoints, the total of the energy "expended" (radiated) by both them is identical. _______________ For clarity I should have included the fact that the total of the energy "expended" (radiated) when equal and matched powers are applied to any and all elemental radiators, of whatever form, essentially is identical. What is NOT identical across these various radiator forms is the field intensity in specific directions in the radiation volume. THAT depends on the design of the radiating structure(s), and the installation+propagation environment. This is the reason for the 1.6 dB advantage in the intrinsic, free- space, peak gain of the full-wave dipole over the 1/2-wave dipole in the NEC analysis I posted earlier today. Both of these configurations radiate the same total energy (somewhere). But along their axes of maximum radiation, the full-wave antenna produces the greater field intensity of the two, for a given applied (and matched) power source. // |
ART vs. W8JI
Art Unwin wrote:
There are no standing waves either If there were no standing waves, a current pickup would read a constant current when moved up and down the conductor, but it doesn't. A current pickup proves there are standing waves. You can see it with your own eyes using RF current meters available from MFJ. If your theory rests on "no standing waves" being present, it can easily be disproved. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
On Sep 4, 6:57*pm, Cecil Moore wrote:
Art Unwin wrote: There are no standing waves either If there were no standing waves, a current pickup would read a constant current when moved up and down the conductor, but it doesn't. A current pickup proves there are standing waves. You can see it with your own eyes using RF current meters available from MFJ. If your theory rests on "no standing waves" being present, it can easily be disproved. -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com I will wait for that day. Regards |
ART vs. W8JI
Art Unwin wrote:
Remember my WL is a closed circuit Believe it or not, there are reflections at the feedpoint caused by the Z0 physical impedance discontinuity. You would be correct only if your "closed circuit" was a traveling wave antenna. But if it was a traveling wave antenna, its feedpoint impedance would be in the hundreds of ohms which, I assume, it is not. The fact that your antenna doesn't have a feedpoint impedance equal to the Z0 of the antenna wire proves that reflections are present. W8JI made essentially the same mistake in his loading coil delay measurements so don't feel bad about it. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
Art Unwin wrote:
I will wait for that day. No need to wait. It's easy to make the measurements for yourself. I have already done it to prove that standing wave current, with its unchanging phase relative to the feedpoint current, cannot be used to measure the phase delay through a loading coil. If a current probe is used to measure a traveling wave, the amplitude will be constant. If the amplitude changes from point to point, it contains a standing wave. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
ART vs. W8JI
Cecil Moore wrote:
Art Unwin wrote: I will wait for that day. No need to wait. It's easy to make the measurements for yourself. I have already done it to prove that standing wave current, with its unchanging phase relative to the feedpoint current, cannot be used to measure the phase delay through a loading coil. If a current probe is used to measure a traveling wave, the amplitude will be constant. If the amplitude changes from point to point, it contains a standing wave. Art? Measure something? You must be kidding. Next you'll expect him to tell us how to build one of his antennas. Then we'd all know for sure what a fraud he is. tom K0TAR |
ART vs. W8JI
On Sep 4, 7:31*pm, tom wrote:
Cecil Moore wrote: Art Unwin wrote: I will wait for that day. No need to wait. It's easy to make the measurements for yourself. I have already done it to prove that standing wave current, with its unchanging phase relative to the feedpoint current, cannot be used to measure the phase delay through a loading coil. If a current probe is used to measure a traveling wave, the amplitude will be constant. If the amplitude changes from point to point, it contains a standing wave. Art? *Measure something? *You must be kidding. Next you'll expect him to tell us how to build one of his antennas. Then we'd all know for sure what a fraud he is. tom K0TAR Tom You are losing it and getting worse. Why don't you block my posts? That way you will not lose any sleep. I just smile when you post but in return you get so angry you don't make much sense it terms of a response Right from the get go all denied that adding a time varying field to Gaussian static theorem provides mathematics of radiation as taught by Maxwell. Until this group recognises this it is pointless to proceed. You will just have to live with that until all can come to terms with that statement.You will not read it in any book so you have to go back to first principles for yourself. If your learning in life is based on rote or memorizing books then you are out of luck. If you can't come to terms on that then it is you who is the fraud Failing that you will just have to rely on intuition instead of mathematical facts |
ART vs. W8JI
Art Unwin wrote:
Tom You are losing it and getting worse. Why don't you block my posts? That way you will not lose any sleep. I just smile when you post but If you think that I, or anyone else, loses sleep over you, you need to cut your ego down to size. tom K0TAR |
ART vs. W8JI
Art Unwin wrote:
On Sep 4, 7:31Â*pm, tom wrote: Cecil Moore wrote: Art Unwin wrote: I will wait for that day. No need to wait. It's easy to make the measurements for yourself. I have already done it to prove that standing wave current, with its unchanging phase relative to the feedpoint current, cannot be used to measure the phase delay through a loading coil. If a current probe is used to measure a traveling wave, the amplitude will be constant. If the amplitude changes from point to point, it contains a standing wave. Art? Â*Measure something? Â*You must be kidding. Next you'll expect him to tell us how to build one of his antennas. Then we'd all know for sure what a fraud he is. tom K0TAR Tom You are losing it and getting worse. "The camel cannot see the crookedness of its own neck." Old Arabic saying. -- Jim Pennino Remove .spam.sux to reply. |
ART vs. W8JI
tom wrote:
Cecil Moore wrote: Art Unwin wrote: I will wait for that day. No need to wait. It's easy to make the measurements for yourself. I have already done it to prove that standing wave current, with its unchanging phase relative to the feedpoint current, cannot be used to measure the phase delay through a loading coil. If a current probe is used to measure a traveling wave, the amplitude will be constant. If the amplitude changes from point to point, it contains a standing wave. Art? Measure something? You must be kidding. Next you'll expect him to tell us how to build one of his antennas. Then we'd all know for sure what a fraud he is. Actually, Art gave me directions for building his 160 meter antenna, the one people call "The Shoebox". SO you're not quite right on that point. I looked at it, and decided that it very closely resembled an EH antenna, with a tuned circuit on top of some coax. Those type of antennas work after a fashion, probably through feed line radiation in this case. So you could likely build it, install it, and make some contacts with it. Whether that makes it a good antenna is up for discussion. I'd probably go with something else. - 73 de Mike N3LI - |
| All times are GMT +1. The time now is 12:27 PM. |
Powered by vBulletin® Copyright ©2000 - 2025, Jelsoft Enterprises Ltd.
RadioBanter.com