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Jerry Martes wrote: Hi Art I hurt my knee, so I have alot of time to spend on this computer right now. I've been trying to develop skills with Roy's EZNEC. Can you send me enough data on your concept as I'd need to model it with EZNEC? Jerry, I am not computor literate in many ways so I dont have the ability to post a page. I am trying to do what you ask but it will takes time, I gave a set up but it did not have any pictures to provide interest for those who have EZNEC so they didn't try out things. I will get something that people can look at possibly using EZNEC which will remove the fear of the unknown from many on this newsgroup. I missed the point about the unsatisfactory aspects of a Yagi antenna. Unsatisfactory is really a relative term. I made a 60 to 80 foot yagi that did a great job in making far off contacts which does get a bit old after a while. The antenna being long took up the slack in the rotor when it was windy was something I didn't like. On top of that the beam width was narrow because of its high gain but if the wind was going I really wasn't getting the benefit of the extra gain because of the slack in the pointing methods and ofcourse with such a long length of antenna it was hard to make corrections over time as we all do with antennas. So My main requirement to seek was a wide beam with little or no sacrifice in gain as well as something shorter to prevent my rotor from taking a beating and most of all I wanted a constant gain over the band so I wasn't at a disadvantage as I moved around. As I said it is all relative and if you want to build an antenna just to0 get on the air it is hard to beat the simplicity of a yagi unless you become to demanding of its performance. Is there any similarity between your "cluster" and the Wullenweber" (?sp?) antenna concept? No. That antenner is really a driven element in conjunction with a detune element. The elements are the vertical variety and if only a single direction of radiation is required then two elements would suffice. But the military wants to point in all directions and sometimes wants to scan in all directions so basically instead of turning a vertically polarised yagi they just align the driven element with one of the multitude of untuned elelemnt arranged in a circle via coax and switching methods instead of a very very long yagi swinging around. How are you able to measure the resistive component of an antenna's terminal impedance then seperate it into two parts? You state that one resistance is related to current below the surface and the other the current that flows on the top of the surface. Well that is where the computor comes in, what would take the likes of me a lifetime to sort out I get a suitable computor program from one of the clever guys around but you must remember a lot of programs were designed around the Yagi with the thought it would always remain as the antenna of choice. There are other programs around that can circumvent the basic yagi design but it requires more effort and knoweledge and most of us are old guys with asn abundance of senior moments. What frequency band do you do your testing on?? You must have some very good test equipment. I do have a lot of equipment but I realise that it is of little use if you cannot rely on the results you obtain, that is the beauty of computor programs as most of the human frailties have been removed. Is it easy for you to tell me why you want to avoid "reactiveness"? I thought I had attempted that! Tell me how I can model your antenna with EZNEC. No I can't since I am not familiar with it but as I said earlier I am trying to get an example done with the use of EZNEC which will provide more meaning to those that are interested tho I do understand that the spamming warfare will increase from those who feel all is known about antennas and it is written right infront of them in their personal books. New books, authors or new ideas are not necessary anymore to many of the old timers Regards Art Jerry "art" wrote in message oups.com... Jerh each otherry What I am doing is to get away from inline coupling of elements. The Yagi antenna is one of these where all the elements are in line. What I am doing is to arrange a a bunch of elements in a group or cluster such that each and all elements couple with each other rather than the the two elements along side. By doing this and yet making the bunch of elements resonant on their own as well as being driven by one element as with the normal antenna you have to make changes in either the length, dia or material of each element to compensate for all the other factors implanted on them by the proximity of all the other elements in the bunch or cluster. When this is done correctly the bunch of elements are in equilibrium with each other and where each element impedance is devoid or has reactance minimised. The reason for this aproach is the two resistances that you encounter are the resistance of the material used for the element which is where the current flows below the surface and the radiation resistance which is from the current that flows on top of the surface to produce radiation. Since it is radiation that we are concerned with only true resistance is of importance and where reactiveness in the impedances provide no benefit to radiation. The bottom line is that we want to avoid reactivenes whereas the yagi by coupling elements that are untuned or not resonant promotes reactiveness. An example of what this reactiveness does to an array is to make the value curves for gain, back to front and swr all peaking at different frequencies where as the ideal arrangement is to have all the curves peak near the same frequency so that when using the antenna across the band you have a fairly consistent gain figure instead of having to cut it at the high or low end of the band in a compromising effort. When building such an array you take advantage of height in the turning radius of the beam since you dont have to place all elements in a single line as with a yagi which imposes limits on antenna length. by utilising height of the array you can have a smaller rotating radius with the same gain of a yagi with a larger turning radius together with a bandwidth with smoothed variables. Hope that helps and clears some of the mystery away from clustered arrays. This aproach by the way also applies to vertical arrays from which you can get horizontal, vertical and circular radiation where each has its special place of use. Use of academic terms was only provided because some academics don't like change and want to see the same things they see in books and for some reason were taught that talk of statics in the same room as electromagnetics is blasphamy yet they cannot bring forward anything in the books that say they are totally separable. By the way I mentioned Nagy where as it should have been Brown who did so much in recent years in broadcasting and T.V. Have fun with antennas and don't get intimidated by those who learned things in College only to memorise and pass exams instead of using knoweledge to advance the quality of life. Best regards Art Jerry Martes wrote: Hi Art Thanks for taking your time to direct me to some very complex thinking. But, I'm a rather simple guy who isnt well educated. You apparently expect a "just regular guy" like me to understand the ccomplex convoluted theoretical stuff that you write about. When I did work as an antenna design engineer, years ago, I saw some of my buddies working on the distribution of energy across apertures in an effort to shape beams. One of their considerations was to decrease the power to the elements as they were more distant from the center of the array. I remember reading that when the power is tapered to provide a distribution about equivalent to a Gaussian Distribution, the side lobes were minimal. I really enjoy thinking about real antenna construction projects. but, when it gets to the Maxwell's Equation kind of analysis, I get lost. I dont even know what a Vector is. You may have the wrong impression about me, Art, I'm an old guy who wants to have fun with antennas. It isnt necessary for you to tell me to "get back to basics". I dont have interest in the "basics" you refer to. Is it possible for you to tell us (me) what you are referring to without referring to Vectors, Gauss's law, Lorentz, "Nagi", and even elementary calculus? Frankly, Art, you confuse me when you write such scholarly paragraphs. You and I are so far removed from each other intellectually that I can never keep up with your texts. Jerry "art" wrote in message ups.com... Jerry, get back to basics and look up a conservative field relative to Gaussian law. Step 1 It is a group of electric charges with an addition vector of zero. So move backwards and remove that vector if you wish and you have a gaussian field of electrical charges which in the case of a bunch of resonant elements can be seen as all positive or all negative charges and we also know that Gaussian law is valid even for enclosed charges in motion. Step 2 The vector that we removed is known as curl but at this time nit has no valu is the samee tho the vector direction is known. Step 3 Faraday's law of Induced electromotive force. This is somewhat opposite to the consevative field in terms of rotation but in relative terms it where the consevative field is revolving around a magnetic field ( hopefully you can visualise this) So we have a charge q in an element of length ds, which element, at the instant considered has velocity u,experiences a force. Now I know some have difficulty with what I said earlier with respect to adding " at an instant of time) to Gausses law which is the same length of time referred to above as " at the instant considered " Gtep 4 We then examine Lorentz equation which refers to an induced electric field which is present when, for example the magnetic field is changing with time such that v1 = 1/q integral F.ds. You can now see that any CONSERVATIVE force that might be included in F would integrate to zero thus ommiting any electrostatic field that might be present Note again faradays law, it is valid regardloess of the nature of the factor or factors responsible for change in magnetic flux. So now the overview of the cluster of resonant elements projected a conservative field with a magnetic vector of zero reflecting" an instant of time" with respect to resonant elements and where the magnetic field will provide motion to the electrostatic field where all charges will exibit the same direction of charge and will change in unison Now no amount of writing will get you to understand this flow of concept if you are not willing to have an open mind or think around something that at the present time you fail to understand and are not willing to rethink thing, possibly in a different way than I presented it. If you are so inclined you can go back further in history and play with the 4 vertical array of elements formed by Nagi to obtain possible insights since he also worked with an array of vertical elements all of which were resonant. His work has been rechecked via Matlab and found to be correct so you have a viable path to follow if you have a modicom of interest in this new concept. It must be noted that the above is only a partial description of the concept because I have yet to add a detuned element for directional purposes for the radiation field. There is nothing more that I can add that will persuade you to follow thru with this concept so I believe I have now reached the Rubicon with respect to this vision of mine. If you can't understand it now put it down to me not being smart enough to explain clearly electromagnetics to those skilled in the art which I am now finding to be a hopeless task at least here in the U.S. unless one can read it in a book and memorise it so one can pass an exam.. Art Jerry Martes wrote: "JIMMIE" wrote in message ups.com... Dave wrote: "art" wrote in message ups.com... In the thread Rain static I referred to a closed surface which is clearly defined by Gauss's law. Gauss's law doesn't define a surface, the surface is any arbitrary surface surrounding a charge. Let us now look at a time vary field applied to a dielectric. I fht efield is applied for the shortest of time the charges will stay on the surface. If time is longer than the shortest space of time you make it sound like there is some 'shortest' time where charges won't move. this is not true. no matter how short you make the time it will move the charges. then charges will openetrate the closed surface. If the surface is an insulator type then it takes a long while to penetrate but if the surface Here you mix up 'surface' and 'surface'. the gauss's law 'surface' is a mathematically useful construction around a charge, it does not have any charge 'on' it, nor is there any 'penetration' of it by charge in gauss's law. it is strictly a non-material thing that is used only for calculation purposes. is a good conductor then the charges will penetrate very quickly so we can associate the time constant of penetration to the subject of skin depth. If we are to associate the time varying field to a gaussian field you have yet to define a 'gaussian field'. gauss's law applies to electric fields and their relation to charges. all the excess charges must be on the surface by law. only in a 'perfect' conductor. dielectrics and 'empty' space can have distributed charges throughout. Or in other words the time evolved must be shorter than the time required to begin penetration. huh? it just goes down hill from here. write some equations, do some drawings, publish a manuscript. all the rest is empty handwaving based on incorrect assumptions and missing definitions. Thus for a short space of time all charges are on the surface and the charges have a magnhe radiating eneetic and electric field vectors. Just having charges is not enough to convert to a gaussian field in that a gaussian field must be in equilibrium thus a cluster of elements must have the direction of the surface charges change in unison. For a cluster of elements to do this they must all be resonant such that the charges reach the ends of the elements at the same time. Resonance of an element is determined by its diameter and its length and because it is coupled to other elements in the cluster the coupling must be taken into account to secure resonance of not only the individual elements but of the cluster as a whole. When this is accomplished the charges on the surface of the closed volume are in equilibrium but onty for that shortest of short time and where that time is added to the gaussian formulae for the transition to be complete. For the Gaussian field or volume we can say the energy inside the gaussian field is equal to that supplied by flux to the outside of the border and remember the flux inside consists of magnetic and electric vectoirs. We now can say that in a moment of time the flux produced from each element that breaches the border in summation with the other elements is equal to the radiating field outside of the border when each element energy makes the transmittion. Thus the summation of each of the clustered elements individual energy when the vectors are given a value must equal the flux on the outside of the border that produces radiation. We also know that if we have a cluster of elements that are clustered together we can obtain radiation by just applying a time varing field to just one of the elements and by virtue of intercoupling all the radiating energy will leave the near field. Thus we have two different methods of determining the value of the radiated field ! radiation from the clustered within a Gaussian field and 2 radiation from an array of coupled elements Since the elements within the cluster are all of the same "Q'" the determination of all factors in the resulting equation are simplified to Ohms law and where the laborious coupling calculations are omitted. The above describes in first principles as to how a Gaussian field in a short space of time can be equated to a radiating cluster using existing laws of the masters which also embraces NEC code. Now many have said I have no understanding of radiation concepts so go ahead and tear this apart and have a merry Xmas doing it Art Unwin KB9MZ..........XG It appears Art has picked up some phrases haphazardly and is trying to apply them to antennas some how, If I remember correctly doesnt Gaussian field apply to statistical distribution. Been a long time since I had statistical analysis back in the early 70s but I think this is also refered to as a "normal distribution". Hi Jimmy By my standards, you are *Right On* on all you wrote. I'm pretty sure Gaussian distribution of power across a radiating plane results (theoretically) in zero side lobes, That is also a very poor distribution when gain is a goal. I think the term Normal is synonymous with Gaussian when referring to aperture distribution. Jerry |