|
skin depth (eddy current/Foucault currentO)
At 3 times the standard depth of skin depth the density is 5 percent
of that on the surface, below which only copper losses with respect to a time varying current. So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
... So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art I think that question is probably best answered with a question(s) ... What is a thin element?; What is a thick element? What is the surface area of the element(s) in question?; what are the power densities involved?; Does the surface quality of the element cause these measurements to vary?; In all cases ever recorded, is it ALWAYS the level you gave, i.e., no anomalies? I have always thought 1/4 copper tubing with a tenalized SS welding wire of heavy gage though its center was superior at high power, a lot get by with much thinner elements. On 10m and lower, I would, generally, use heavy wall copper pipe of 1/2", or so ... on wifi antennas, I use 1/8 heavy wall brass hobby tubing--I suspect no advantage over thin wall. I would love access to facilities to investigate this, that lacking, I would love data I could trust ... what do you find so interesting that rf might be forced deeper into the surface of elements? I assume from all my readings and studies that rf prefers the surface--the higher the freq(s) the more the phenomenon is noted/enforced. Regards, JS |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
At 3 times the standard depth of skin depth the density is 5 percent of that on the surface, below which only copper losses with respect to a time varying current. So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art Babble. Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth -- Jim Pennino Remove .spam.sux to reply. |
skin depth (eddy current/Foucault currentO)
On Dec 5, 6:38*pm, John Smith wrote:
Art Unwin wrote: ... So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? *Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art I think that question is probably best answered with a question(s) ... What is a thin element?; *What is a thick element? *What is the surface area of the element(s) in question?; what are the power densities involved?; *Does the surface quality of the element cause these measurements to vary?; *In all cases ever recorded, is it ALWAYS the level you gave, i.e., no anomalies? I have always thought 1/4 copper tubing with a tenalized SS welding wire of heavy gage though its center was superior at high power, a lot get by with much thinner elements. *On 10m and lower, I would, generally, use heavy wall copper pipe of 1/2", or so ... on wifi antennas, I use 1/8 heavy wall brass hobby tubing--I suspect no advantage over thin wall. I would love access to facilities to investigate this, that lacking, I would love data I could trust ... what do you find so interesting that rf might be forced deeper into the surface of elements? *I assume from all my readings and studies that rf prefers the surface--the higher the freq(s) the more the phenomenon is noted/enforced. Regards, JS Well John the impedance gets lower as the percent of the wavelength goes down Exercising limits when the radiation surface is zero then so is the radiation The point I am stating is that a fractional wavelength is less that a wavelength and copper losses thru the center is less than an ohm so where is there a lesser impedance route fot the current to travel to become a closed circuit without radiating? I am just making the point again that antenna knoweledge on this newsgroup is very sparce Most do not accept I sq R jn all cases,and most will not accept the existence of a Faraday cage! RF does prefer to exist on the surface if and only if contra forces cannot be over come. But then "engineers are not scientists" according to one poster so perusal of white papers is not necessary as the truth is unimportant. So the single question again........ What is the lowest resistance part from the top of a fractional wavelength antenna to obtain a closed circuit? Simple and to the point and no word games as the application of true true science is indicated to those thus qualified Art |
skin depth (eddy current/Foucault currentO)
On Dec 5, 7:01*pm, wrote:
Art Unwin wrote: At 3 times the standard depth of skin depth the density is 5 percent of that on the surface, below which only copper losses with respect to a time varying current. So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art Babble. Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth -- Jim Pennino Remove .spam.sux to reply. Good grief. wilkipedia that you refered to is absolutelly correct I am looking for somebody well vested in RF. If you can point to an error in the given mathematics text then you can regain my respect. Pretty hard to do without a modern college education in physics or electrical engineering Next self perceived expert come forward. Art |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
On Dec 5, 7:01Â*pm, wrote: Art Unwin wrote: At 3 times the standard depth of skin depth the density is 5 percent of that on the surface, below which only copper losses with respect to a time varying current. So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art Babble. Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth -- Jim Pennino Remove .spam.sux to reply. If you can point to an error in the given mathematics text What "given mathematics text"? -- Jim Pennino Remove .spam.sux to reply. |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
... Art I expected someone to pop-in with an ultra-simplistic explanation, and poof!; Claim the problem explained ... I myself pay enough attention that, I can see the point you make. Indeed, anyone with even half-a-brain, interested in rf and having worked with antennas in a hands-on reality, i.e., build rather than buy, would have come across this enigma. Real world example: I have watched amateurs pump 1+KW into, what I consider, incredibly thin elements/conductors (my math skills indicate current carrying capacity of the wire is being vastly exceeded, at points/nodes.) And, it has struck me that I don't see this element vaporize at a current node! Indeed, I don't even see a pronounced sag/heating/softening of such elements ... The simple/short explanation makes all our "antenna prophetic/predicting" formulas and equations work ... the long explanation is a bit more complex, me thinks ... Regards, JS |
skin depth (eddy current/Foucault currentO)
On Dec 5, 8:01*pm, wrote:
Art Unwin wrote: On Dec 5, 7:01*pm, wrote: Art Unwin wrote: At 3 times the standard depth of skin depth the density is 5 percent of that on the surface, below which only copper losses with respect to a time varying current. So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art Babble. Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth -- Jim Pennino Remove .spam.sux to reply. If you can point to an error in the given mathematics text What "given mathematics text"? -- Jim Pennino Remove .spam.sux to reply. What you pointed to as being contrary to what I stated Silly statement with a liberal smattering of "bable" does nothing to suggest that you are up to date education in the art. Next please Art |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
On Dec 5, 8:01Â*pm, wrote: Art Unwin wrote: On Dec 5, 7:01Â*pm, wrote: Art Unwin wrote: At 3 times the standard depth of skin depth the density is 5 percent of that on the surface, below which only copper losses with respect to a time varying current. So what exactly forces a time varying current to take an alternate route of travel from the center of a conductor when the resistance is so low compared to other routes that could be taken.? Note : center resistance is lower than that on the surface because skin depth (opposing eddy currents) cannot form. Art Babble. Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth -- Jim Pennino Remove .spam.sux to reply. If you can point to an error in the given mathematics text What "given mathematics text"? -- Jim Pennino Remove .spam.sux to reply. What you pointed to as being contrary to what I stated What I pointed to wasn't a "mathematics text" and if it is contrary to what you stated, that is because your statements are babbling nonsense. -- Jim Pennino Remove .spam.sux to reply. |
skin depth (eddy current/Foucault currentO)
On Dec 5, 8:09*pm, John Smith wrote:
Art Unwin wrote: * ... Art I expected someone to pop-in with an ultra-simplistic explanation, and poof!; *Claim the problem explained ... I myself pay enough attention that, I can see the point you make. Indeed, anyone with even half-a-brain, interested in rf and having worked with antennas in a hands-on reality, i.e., build rather than buy, would have come across this enigma. Real world example: I have watched amateurs pump 1+KW into, what I consider, incredibly thin elements/conductors (my math skills indicate current carrying capacity of the wire is being vastly exceeded, at points/nodes.) *And, it has struck me that I don't see this element vaporize at a current node! Indeed, I don't even see a pronounced sag/heating/softening of such elements ... The simple/short explanation makes all our "antenna prophetic/predicting" formulas and equations work ... the long explanation is a bit more complex, me thinks ... Regards, JS John., there are one or two who can provide the correct answer. One is an old timer on this group from years ago who I believe is well versed in RF and has made a couple of postings lately. Funny thing is that when an addition was made to electrical laws by Heaviside and Maxwell it was just an addition to bring the laws into equilibrium! Ofcourse, those units encompassed a formula well suited for a displacement current. However the idea of waves versus particles exist to this very day even when Foucualt discovered the presence of a separate current that fit the initial addition by Maxwell and searched for so long by Einstein before abandoning classical physics and plunged it to relativism for the answer on the understanding that the "weak force" was part and parcel of radiation and a subset of an existing force. He died and there is nobody left to apply authoritity to his thoughts. I can just imagine what woild have happened if Einstein extended the static law by making it a dynamic field which by its equivalent to Maxwell would have placed particles and equilibrium firmly into radiation. Just imagine Einstein having possesion of a computer program of today with optimizer that excluded planar designs in the face of an array in equilibrium. I know of nobody familiar with the present antenna programs who can explain the addition of the "'Weak force" that creats arrays in equilibrium without a hint of parallelism or planar construction. Have all the antenna computer programmers also died or do they have a quiet distrust of their work with respect to Maxwell ? Now we have the relevalation that Neutrinos DO actually have mass obtained frtom the Sun which puts another nail in the coffin with respect to waves. Yes, American Universities deserve their failing grade.( Read Asimov thoughts on present science teaching) NEXT engineer scientist/rocket engineer or what ever Art Unwin KB9MZ....,..,.xg (uk) |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
... Have all the antenna computer programmers also died or do they have a quiet distrust of their work with respect to Maxwell ? Now we have the relevalation that Neutrinos DO actually have mass obtained frtom the Sun which puts another nail in the coffin with respect to waves. Yes, American Universities deserve their failing grade.( Read Asimov thoughts on present science teaching) NEXT engineer scientist/rocket engineer or what ever Art Unwin KB9MZ....,..,.xg (uk) Actually, no, general programmers fill the planet, competition for work is high ... well, perhaps better in china, india, etc. :-( However, programmers "don't much" appreciate programs which play horseshoes. We like EXACT answers, exact measurements and routines which CONSISTENTLY return EXACT figures, dimensions, etc. ... in true math there is but one answer, artists see things in gray, programmers in black and white. When a program says, "Well, you start here, with this measurement, and prune, or lengthen", or, "You start with this capacitance (or inductance) and then adjust as necessary", I feel ill. Example: IF Pi X 3 = circumference ever fails (I expect it to be just as accurate for a 1 inch circle as a 1 million mile one), or returns a "figure to begin experimenting from", I will see it as only a guess also ... and requiring an artist to deduce. Antenna design parameters are a nightmare ... indeed, since that which is not a science is an art--antenna design looks very much an art to me .... or, at least mixed fields of discipline are required. Now, one Art should recognize another art ... grin And, I am done with this whole discussion, someday we will have accurate tools to work with ... end of story. Regards, JS |
skin depth (eddy current/Foucault currentO)
JP wrote:
Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth The Wikipedia treatment is not incorrect, but it may create a false impression that the skin effect is limited to some particular type or cross-section of conductor. There is a more general derivation by Davidson that has far fewer restrictions about the assumed geometry. There is a scanned copy at: http://www.ifwtech.co.uk/g3sek/misc/skin.htm Davidson shows much more clearly that the existence of a skin effect does not depend on any particular shape or size of conductor, or any particular type of electrical circuit. If RF current is flowing in a conductor - regardless of the reason - then the skin effect will be present. That is a very powerful conclusion. Because we know the skin effect will be present, it helps us to trace the RF current pathways on complex shapes such as coaxial cables and shielded loops. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
skin depth (eddy current/Foucault currentO)
"Art Unwin" wrote in message ... On Dec 5, 8:09 pm, John Smith wrote: I know of nobody familiar with the present antenna programs who can explain the addition of the "'Weak force" that creats arrays in equilibrium without a hint of parallelism or planar construction. Have all the antenna computer programmers also died or do they have a quiet distrust of their work with respect to Maxwell ? nope, us programmers are perfectly happy, you on the other hand should completely distrust any computer program modelling antennas out there... NONE of them include the weak force, therefore they should not be trusted to model your magical equilibrium antennas. you must go off and find a different way to calculate your antenna patterns that does include the weak force. Now we have the relevalation that Neutrinos DO actually have mass obtained frtom the Sun which puts another nail in the coffin with respect to waves. the only place that has been revealed is to your in your delusional dreams. go publish that in a peer reviewed scientific journal and see how many cups of coffee it gets you. |
skin depth (eddy current/Foucault currentO)
On Dec 6, 2:38*am, Ian White GM3SEK wrote:
JP wrote: Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth The Wikipedia treatment is not incorrect, but it may create a false impression that the skin effect is limited to some particular type or cross-section of conductor. There is a more general derivation by Davidson that has far fewer restrictions about the assumed geometry. There is a scanned copy at:http://www.ifwtech.co.uk/g3sek/misc/skin.htm Davidson shows much more clearly that the existence of a skin effect does not depend on any particular shape or size of conductor, or any particular type of electrical circuit. If RF current is flowing in a conductor - regardless of the reason - then the skin effect will be present. That is a very powerful conclusion. Because we know the skin effect will be present, it helps us to trace the RF current pathways on complex shapes such as coaxial cables and shielded loops. -- 73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek Thank you very much for the addition supplied. I never really understood why hams could not accept this From my point oif view the beauty of the Foulcalt or eddy current is without this "pealing" on the chemical adhesion effect that a particle has on a diamagnetic surface the ejected particle would be without spin, and as such would not be able to have straight line projection within a gravitational field, a necessity for radiation. Any book on wave guides will picture this eddy current on the inside walls and any book on non destructive testing will also corroberate its presence and yet it is still rejected by this group. When Maxwell inserted the required units to achieve equilibrium per Newton it was the mathematics that forcast the presence of a levitation force that would not be identified for several decades but stil ignored because of the dominance of wave theory. Cheers Art |
skin depth (eddy current/Foucault currentO)
On Dec 6, 6:31*am, "Dave" wrote:
"Art Unwin" wrote in message ... On Dec 5, 8:09 pm, John Smith wrote: I know of nobody familiar with the present antenna programs who can explain the addition of the "'Weak force" that creats arrays in equilibrium without a hint of parallelism or planar construction. Have all the antenna computer programmers also died or do they *have a quiet distrust of their work with respect to Maxwell ? nope, us programmers are perfectly happy, you on the other hand should completely distrust any computer program modelling antennas out there... NONE of them include the weak force, therefore they should not be trusted to model your magical equilibrium antennas. *you must go off and find a different way to calculate your antenna patterns that does include the weak force. Now we have the relevalation that Neutrinos DO actually have mass obtained frtom the Sun which puts another nail in the coffin with respect to waves. the only place that has been revealed is to your in your delusional dreams. go publish that in a peer reviewed scientific journal and see how many cups of coffee it gets you. No Siree, it has been several years that the idea of Neutrinos without mass was squashed. Two years ago it was again confirmed in experiments in Batavia, Illinois. And ofcourse it gives CERN its impetus for their current experiments in Switzerland Pull yourself together David As for publishing academics require a reference lists of quotes from other members of academia and are loath to challenge prior papers and academics. Thus to be published you must stay on the same track as others with no going back for solid review. History shows that papers supplied by non members of academia will never be accepted in their life time. That is why I say papers should be open source and open to challenge from those outside academia. Art |
skin depth (eddy current/Foucault currentO)
"Art Unwin" wrote in message ... That is why I say papers should be open source and open to challenge from those outside academia. go challenge anything you want... it sounds like you don't want or need to reference any current papers since your theory goes against everything that is accepted, so just publish away. you have a web site, put something on there that is testable and see if anyone can prove it. or better yet, apply for another patent with something useful and see if anyone buys it. your magical levitating weak force neutrinos make for a good laugh now and then, but are otherwise total fantasy until you can show the equations... and not a single reputable publication will accept a paper from you without those equations. |
skin depth (eddy current/Foucault currentO)
"Art Unwin" wrote
Thank you very much for the addition supplied. I never really understood why hams could not accept this. _______ Not just hams, Art. Skin depth applies to a-c energy flowing along a conductor. The same principles of physics apply no matter to which end of a conductor that a-c is applied. That is, the a-c energy reflected from the unterminated end of a conductor will travel on its outside for the same reason it traveled on the outside of that conductor when first applied to it, at its other end. Fractional wavelength conductors and your "equilibrium" are irrelevant to this. The center conductor of rigid coaxial transmission line used in the broadcast industry is hollow, because it can carry the same amount of a-c energy as it could if it was solid (and costs/weighs a lot less). RF |
skin depth (eddy current/Foucault currentO)
Art wrote:
"When Maxwell inserted the required units to acheive equilibrium per Newton it was the mathematics that forcast the presence of a levitation force that would not be identified for several decades but still ignored because of the dominance of wave theory." Maxwell found his equations had the form of those predicting behavior of water waves and they correctly predicted the velocity of light as previously determined. Maxwell was a mathematician and a physicist who searched for things with practical applications. In one of Maxwell`s lectures he said: "Now, Professor Graham Bell, the inventor of the telephone, is not an electrician who found out how to make a tin plate speak, but a speaker, who to gain his private ends, has become an electrician." Maxwell`s equations are adequate to solve all questions of radio waves at once in place of a multitude of their predecessors. Art even agrees they work as a basis for antenna programs in computers however he spells computer. Using the tried and proven until something better comes along is common sense. From what i`ve seen, wave theory works well for large scale predictions while the particle theory seems to work at the atomic scale. Too bad Cern had an instantaneous multimillion dollar breakdown. A.G. Bell produced the most valuable patent in history. What are the results of the Unwin patents? Best regards, Richard Harrison, KB5WZI |
skin depth (eddy current/Foucault currentO)
Art wrote:
"So what exactly forces a time varying current to take an alternate route of travel from the center of the conductor when the resistance is so low compared to other routes that could be taken?" Opposing ac current is total impedance, not just resistance. The deepest fibers in a conductor are encircled by the largest number magnetic flux linkages. These create a reactance which generates a counter-emf opposing an imposed current. The deeper the depth inside a conductor, the greater the opposition to the imposed current. Look for "skin effect" in any edition of Terman and you will find diagrams illustrating the various magnetic flux paths inside the conductor which cause skin effect. Best regards, Richard Harrison, KB5WZI |
skin depth (eddy current/Foucault currentO)
On Dec 9, 12:53*pm, (Richard Harrison)
wrote: Art wrote: "When Maxwell inserted the required units to acheive equilibrium per Newton it was the mathematics that forcast the presence of a levitation force that would not be identified for several decades but still ignored because of the dominance of wave theory." Maxwell found his equations had the form of those predicting behavior of water waves and they correctly predicted the velocity of light as previously determined. Maxwell was a mathematician and a physicist who searched for things with practical applications. In one of Maxwell`s lectures he said: "Now, Professor Graham Bell, the inventor of the telephone, is not an electrician who found out how to make a tin plate speak, but a speaker, who to gain his private ends, has become an electrician." Maxwell`s equations are adequate to solve all questions of radio waves at once in place of a multitude of their predecessors. Art even agrees they work as a basis for antenna programs in computers however he spells computer. Using the tried and proven until something better comes along is common sense. From what i`ve seen, wave theory works well for large scale predictions while the particle theory seems to work at the atomic scale. Too bad Cern had an instantaneous multimillion dollar breakdown. A.G. Bell produced the most valuable patent in history. What are the results of the Unwin patents? Best regards, Richard Harrison, KB5WZI * * |
skin depth (eddy current/Foucault currentO)
On Dec 9, 12:53*pm, (Richard Harrison)
wrote: Art wrote: "When Maxwell inserted the required units to acheive equilibrium per Newton it was the mathematics that forcast the presence of a levitation force that would not be identified for several decades but still ignored because of the dominance of wave theory." Maxwell found his equations had the form of those predicting behavior of water waves and they correctly predicted the velocity of light as previously determined. This seems a distortion of the facts. The addition was seen as the forces between current and the force between static particles which was in fact a confirmation of the the speed of light. My understanding of the term eddy current with respect to waves was that it was ,made much later. But the realization of the connection to light should have really been recognised by Maxwell as a displacement of particles and not waves since the presence of particles is predetermined. This lack of understanding alsio helped the incorrect determination of light being a formation of waves instead of particles. This by the way also cements the validity of changing Gauss's law of statics to a dynamic field to equate with Maxwells laws which also confirms the presence of particles. Another correlation to my theory is the interaction of particles with the Earths magnetic field to produce Aurora or Northern Lights i.e. particles bombardmentnot waves, Same goes for light created at the center of a tornado which in itself is the "eddy current" of a storm where againb light is seen as a lightning strike where particles plus moisture is drawn into the stratoshere an d then become separated. The evidence just piles up that radio communication, radar and light itself is that which comes from particles ala Neutrinos and NOT from the formation of magnetic or electrical waves. And that Einstein was correct in his assertion that radiation held the key for the Universal laws of all the sciences of nature.Later when Foucalt discovered "Eddy current" which he associated with water eddy currents it then came into use as a non destructive material measurement system together with use in aluminum sorting in scrap yards which in essence is a macro demonstration of particle presence in radiation., again a vindication that the Maxwell addition was wrongly assumed a wave structure. I won't comment on your following statements as it is lost on me why you have quoted them and the point of stating them Maxwell was a mathematician and a physicist who searched for things with practical applications. In one of Maxwell`s lectures he said: "Now, Professor Graham Bell, the inventor of the telephone, is not an electrician who found out how to make a tin plate speak, but a speaker, who to gain his private ends, has become an electrician." Maxwell`s equations are adequate to solve all questions of radio waves at once in place of a multitude of their predecessors. Art even agrees they work as a basis for antenna programs in computers however he spells computer. Using the tried and proven until something better comes along is common sense. From what i`ve seen, wave theory works well for large scale predictions while the particle theory seems to work at the atomic scale. Too bad Cern had an instantaneous multimillion dollar breakdown. A.G. Bell produced the most valuable patent in history. What are the results of the Unwin patents? Best regards, Richard Harrison, KB5WZI * * |
skin depth (eddy current/Foucault currentO)
On Dec 9, 3:39*pm, (Richard Harrison) wrote:
Art wrote: "So what exactly forces a time varying current to take an alternate route of travel from the center of the conductor when the resistance is so low compared to other routes that could be taken?" Opposing ac current is total impedance, not just resistance. I tthink you have to go back to the beginning of this thread as again you are talking out of context. My statement referes to the current path on a fractional waqve antenna when it reaches the top. My point was that the current then procedes to the INSIDE of the radiator where the AC current cannot produce an eddy current and thus the opposition to current flow in the centre is just a copper loss i.e.resistance. This statement was made in requesting a possible different current path from the top of the radiator that provided a lower resistive path. I.E I pointed out that the impedance dropped linearly with respect to radiator length and thus I wanted a mathematically demonstrated different path that would counter my initial assertion. The deepest fibers in a conductor are encircled by the largest number magnetic flux linkages. These create a reactance which generates a counter-emf opposing an imposed current. The deeper the depth inside a conductor, the greater the opposition to the imposed current. I think I have stated what skin depth is and what created it many times so I won't respond to the above paragraph Look for "skin effect" in any edition of Terman and you will find diagrams illustrating the various magnetic flux paths inside the conductor which cause skin effect. I believe that the Wilkedia URL and Ian's supplied scanned page is adequate descriptions where the initial supplied current is the sum of the two currents in the circuit one of which is Maxwells determination of displacement current i.e.a current that displaces while providing an accelleration to PARTICLES (charges) from the surface of a radiator. If you can give an specific answer in mathematical form to the initial question asked it would be apreciated Other than that there is no need for continuation of this thread. Best regards, Richard Harrison, KB5WZI |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
Other than that there is no need for continuation of this thread. There was no need to start it in the first place. -- Jim Pennino Remove .spam.sux to reply. |
skin depth (eddy current/Foucault currentO)
Art Unwin wrote:
On Dec 6, 2:38*am, Ian White GM3SEK wrote: JP wrote: Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth The Wikipedia treatment is not incorrect, but it may create a false impression that the skin effect is limited to some particular type or cross-section of conductor. There is a more general derivation by Davidson that has far fewer restrictions about the assumed geometry. There is a scanned copy at:http://www.ifwtech.co.uk/g3sek/misc/skin.htm Davidson shows much more clearly that the existence of a skin effect does not depend on any particular shape or size of conductor, or any particular type of electrical circuit. If RF current is flowing in a conductor - regardless of the reason - then the skin effect will be present. That is a very powerful conclusion. Because we know the skin effect will be present, it helps us to trace the RF current pathways on complex shapes such as coaxial cables and shielded loops. -- 73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek Thank you very much for the addition supplied. I never really understood why hams could not accept this From my point oif view the beauty of the Foulcalt or eddy current is without this "pealing" on the chemical adhesion effect that a particle has on a diamagnetic surface the ejected particle would be without spin, and as such would not be able to have straight line projection within a gravitational field, a necessity for radiation. Any book on wave guides will picture this eddy current on the inside walls and any book on non destructive testing will also corroberate its presence and yet it is still rejected by this group. When Maxwell inserted the required units to achieve equilibrium per Newton it was the mathematics that forcast the presence of a levitation force that would not be identified for several decades but stil ignored because of the dominance of wave theory. Cheers Art I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
skin depth (eddy current/Foucault currentO)
I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek And he's been at it for several years now. I plonked him well over a year ago. If everyone would stop paying him any attention and stop responding to his BS, it wouldn't take him a month to go bother some other newsgroup that would give him the audience he thinks he needs. We'd be far better off for it. Art's a nut case. Face it and ignore him. PLEASE! W4ZCB |
skin depth (eddy current/Foucault currentO)
Harold E. Johnson wrote:
I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek And he's been at it for several years now. I plonked him well over a year ago. If everyone would stop paying him any attention and stop responding to his BS, it wouldn't take him a month to go bother some other newsgroup that would give him the audience he thinks he needs. We'd be far better off for it. Art's a nut case. Face it and ignore him. PLEASE! I don't normally read a single word from Art, so my original posting was in response to someone else. But when he claims I agree with him, that is more provocation than a man can stand. -- 73 from Ian GM3SEK |
skin depth (eddy current/Foucault currentO)
On Dec 10, 4:37*am, Ian White GM3SEK wrote:
Art Unwin wrote: On Dec 6, 2:38*am, Ian White GM3SEK wrote: JP wrote: Skin depth and what cause it: http://en.wikipedia.org/wiki/Skin_depth The Wikipedia treatment is not incorrect, but it may create a false impression that the skin effect is limited to some particular type or cross-section of conductor. There is a more general derivation by Davidson that has far fewer restrictions about the assumed geometry. There is a scanned copy at:http://www.ifwtech.co.uk/g3sek/misc/skin.htm Davidson shows much more clearly that the existence of a skin effect does not depend on any particular shape or size of conductor, or any particular type of electrical circuit. If RF current is flowing in a conductor - regardless of the reason - then the skin effect will be present. That is a very powerful conclusion. Because we know the skin effect will be present, it helps us to trace the RF current pathways on complex shapes such as coaxial cables and shielded loops. -- 73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek Thank you very much for the addition supplied. I never really understood why hams could not accept this From my point oif view the beauty of the Foulcalt or eddy current is without this "pealing" on the chemical adhesion effect that a particle has on a diamagnetic surface the ejected particle would be without spin, and as such would not be able to have straight line projection within a gravitational field, a necessity for radiation. Any book on wave guides will picture this eddy current on the inside walls and any book on non destructive testing will also corroberate its presence and yet it is still rejected by this group. When Maxwell inserted the required units to achieve equilibrium per Newton it was the mathematics that forcast the presence of a levitation force that would not be identified for several decades but stil ignored because of the dominance of wave theory. Cheers Art I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek Ian I never stated that you supported anything with respect to my ideas. What you supplied with respect to skin effect was a coroberation of the Wilkpedia definition which I stated WAS correct also in the face of a statement that said otherwise. And I thanked you for supplying it and no more. You may call me delusional as a sample of free speech but you like the others have never supplied an iota of evidence that shows that my ideas have zero merit and thus are indulging in childish attacks. I know that you posses the AO antenna computer program and feel very comfortable with the fact that you are capable of putting in a one liner that shows that a radiator for maximum efficiency will be devoid of parallelism. Unless you initially guide a antenna optimiser towards a planar design the program will respond with a non planar design That is a fact and is not delusional. Statements like that is no more than support for the many talking heads. This is a ideal place to point out once and for all a basic fact that points to the feasability of my analysis.To deny or try to cover up this computor fact with respect to the avoidance of a planar design because of the addition to general laws by Maxwell is understandable by those who do not have the means to challenge the books is understandable but for you there is absolutely no excuse and shows a dependence on emotion while at the same time pushing aside scientific fact a fact that that is undeniable. A planar design is a approximation with respect to Maxwells laws. A antenna omptimisation, if allowed, will always respond with a NON planar design to conform with all aspects provided by Maxwell's laws which I might add includes the addition iof the "weak" force as suspected by Einstein. Art Unwin KB9MZ.........XG (uk) |
skin depth (eddy current/Foucault currentO)
"Harold E. Johnson" wrote in message news:RqO%k.418421$TT4.255567@attbi_s22... I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek And he's been at it for several years now. I plonked him well over a year ago. If everyone would stop paying him any attention and stop responding to his BS, it wouldn't take him a month to go bother some other newsgroup that would give him the audience he thinks he needs. We'd be far better off for it. Art's a nut case. Face it and ignore him. PLEASE! W4ZCB but its so much fun to drag new details of his amazing jumping diamagnetic neutrinos out of him! |
skin depth (eddy current/Foucault currentO)
Dave wrote:
"Harold E. Johnson" wrote in message news:RqO%k.418421$TT4.255567@attbi_s22... I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek And he's been at it for several years now. I plonked him well over a year ago. If everyone would stop paying him any attention and stop responding to his BS, it wouldn't take him a month to go bother some other newsgroup that would give him the audience he thinks he needs. We'd be far better off for it. Art's a nut case. Face it and ignore him. PLEASE! W4ZCB but its so much fun to drag new details of his amazing jumping diamagnetic neutrinos out of him! Mocking people like Art isn't my idea of fun. 73, Tom Donaly, KA6RUH |
skin depth (eddy current/Foucault currentO)
And he's been at it for several years now. I plonked him well over a year ago. If everyone would stop paying him any attention and stop responding to his BS, it wouldn't take him a month to go bother some other newsgroup that would give him the audience he thinks he needs. We'd be far better off for it. Art's a nut case. Face it and ignore him. PLEASE! W4ZCB but its so much fun to drag new details of his amazing jumping diamagnetic neutrinos out of him! Mocking people like Art isn't my idea of fun. 73, Tom Donaly, KA6RUH I agree wholeheartedly. Before Art, did you get your jollys pulling the wings off flies? Or just tripping folks who were trying to get around on a pair of crutches? W4ZCB |
skin depth (eddy current/Foucault currentO)
Tom Donaly wrote:
... Mocking people like Art isn't my idea of fun. 73, Tom Donaly, KA6RUH You were raised well, and stand in tribute to your parents; Good man! Very rare these days ... Regards, JS |
skin depth (eddy current/Foucault currentO)
On Dec 10, 6:16*am, "Harold E. Johnson" wrote:
I only just read this reply. NOTHING that I have said or referenced supports Art's ideas in any way. His ideas are totally deluded. -- 73 from Ian GM3SEK * * * * 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek And he's been at it for several years now. I plonked him well over a year ago. If everyone would stop paying him any attention and stop responding to his BS, it wouldn't take him a month to go bother some other newsgroup that would give him the audience he thinks he needs. We'd be far better off for it. Art's a nut case. Face it and ignore him. PLEASE! W4ZCB Harold, Yes I do need an audience of radio hams of which a very small minority is able to operate a computer program for antennas with a optimizer. I may well be a nut case as you say and delusional as others would say but for many years I have presented the same problem to this group which in itself provides vindication to my thinking. Over the years I have pointed out to this group that an optimizer program ( one of which is free on the web) will always discard the planar design in favor of a design that is in equilibrium. Now I am not a computer programer sio I am not resposible for the programs that push aside planar designs such as the Yagi, I am just pointing out a fact. Now I am not willing to take the aproach of garbage in garbage out but I am willing to investigate why and present my findings. I have done that and regardles what you think of me as a person as radio hams you should be concerned about accepted programs on antennas putting out what you consider as garbage. Now I understand that many are not able to tackle such a problem and in fact many cannot even operate a computer. But this is a newsgroup for the discussion of antennas and many feel they are competant to determine what is garbage or not without the use of a computer. But surely some must realize that those who one suspects is really an expert in antennas and computer programs not one has inserted a one liner in a program to check out the info that I placed before them.It has been several years of name calling by those who are not skilled in the art but total silence from those that are skilled because they cannot provide a reason for such results and at the same time cannot aliign themselves with the naysayers. Think about it guys, you want to shut me up then why not explain the anomoly? Years ago hams were happy to accept outrageous gain figures advertized in QST and advertizers knew that hams would not question it and they were correct as the present situation shows. You state I have been a problem for years with respect to this yet nobody as yet has stated that the programs do not take this path or tried to explain why. It takes 5 minuits to check with a one liner and for a hero to emerge to chop me off at the knees, but not one is willing to come forward and thus lose his place in the pecking line of pseudo experts....not one. Thus those on the group of lesser abilities gain confidence in calling evrything trash while those that can do remain silent. They know the computer programs are acting this way. Their silence infers that the programs are doing something "wrong" Harold, turning a blind eye to what i have informed others will not force me to collect coals from Newcastle as I am not going away so a few may maintain an un truth. If you are not just a talking head use the free program available on the net and find out the truth for yourself instead of being a lemming. Art |
skin depth (eddy current/Foucault currentO)
On Wed, 10 Dec 2008 19:58:14 -0800 (PST), Art Unwin
wrote: I may well be a nut case as you say and delusional as others would say but for many years I have presented the same problem to this group which in itself provides vindication to my thinking. Well, if this is a defense, at least it is rational (doesn't mean it is logical, however). Over the years I have pointed out to this group that an optimizer program ( one of which is free on the web) And one that Art will never divulge the name of - with his natural inclination to suppress information. I could be wrong in that he might be actually suborning the circulation of software pirated from vendors. As his experience is limited to one package from the 1980s, and that author has refused to market it anymore because of piracy, it is rather hypocritical that Art suggest it can be freely obtained. Art can immediately nullify this tarnished image of supporting computer piracy by naming this so-called "free optimizer" - but I will bet dollars to donuts that he would rather embrace this form of illegality than utter that "free optimizer's" name. will always discard the planar design in favor of a design that is in equilibrium. In fact it will NEVER discard any design for one that is inferior! Now I am not a computer programer sio I am not resposible for the programs that push aside planar designs such as the Yagi, A computer user is probably more dangerous than a computer programmer when it comes to this erroneous usage. I am just pointing out a fact. Making a mistake is a fact. Publishing it as the tool's fault is called coppin' a plea. Now I am not willing to take the aproach of garbage in garbage out but I am willing to investigate why and present my findings. Another strange defense garroted by the fantasy of "findings." 73's Richard Clark, KB7QHC |
skin depth (eddy current/Foucault currentO)
"Art Unwin" wrote in message ... It takes 5 minuits to check with a one liner yeah, and art thinks he is the only one who ever let an optimizer run until it went into an unrealizable super gain state. most of us have learned to constrain them properly so they give buildable results, but not art, he keeps trying to explain how they use the same well known maxwell equations, but in secret have this hidden weak force that makes them give results that only he can understand. |
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