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Light,Lazers and HF
On Sep 11, 2:04*pm, Art Unwin wrote:
On Sep 10, 10:56*pm, wrote: On Sep 10, 10:29*pm, Art Unwin wrote: On Sep 10, 9:23*pm, Art Unwin wrote: On Sep 10, 8:45*pm, wrote: Art Unwin wrote: What is the main factor that prevents HF radiation from focussing for extra gain? Money. If you can afford to build a 20m parabola about 2,000 feet in diameter and the place to mount it, you'll get lots of gain. -- Jim Pennino Remove .spam.sux to reply. Then are you saying it is the antenna size that is the main factor?.. So my antenna which is physically small can be focussed on a dish which would provide straight line radiation or a radiation beam? Working on a single element on the ground with a optimizer instead of a half sphere I got a straight vertical line at the sides which suggested a gun barrel radiation with a perfect earth as the reflector. Gain was around 8db vertical which is why the question regarding focussing! If it was properly focussed the gain should be more. 2000 foot dish seems somewhat odd, probably based on a "straight" wavelength and not a small volume in equilibriumas the directer right? Art Let me ask the question another way. Whether it is believed or not, if a 80 Metre antenna was compressed to the size of a couple of shoe boxes would the dish be reduced in size accordingly? Regagards Art- Hide quoted text - - Show quoted text - No. The shoebox size antenna would approximate an isotropic if it did radiate. It would still have to be placed at the focal point of a very large parabola due to the size of the wave length. Such an antenna, I believe, on the island of Puerto Rico (the SETI antenna) although it is currently used primarily as a receiving antenna. That parabola is positioned to have a very high radiation angle and might not be be that good for terrestrial DX. The antenna at PR has a stable reflector and a moveable receiver thus the take off angle depends on the angular position of the receiver and the center of the reflector. The receiver is moved regularly so the sky can be traversed for listening. This was the idea when the antenna *was set up initialy by Princeton University before they gave up possesion of it. With respect to WL no facts have been presented to support that fact. If you go back to the arbitrary border analysis a force thru the paper of the center of the border will present resultant forces around the outside of the border representing ripples on water in wave like fashion, that does not correlate to the ejection *of a particle thru a fissure in the border. Mixing apples and oranges no less Nuf said- Hide quoted text - - Show quoted text - That is interesting. I thought the PR dish was parabolic. As a parabola, the reflected waves (or particles if you will) of a transmitter at focal point can only traverse in one direction, that is, in a direction parallel to the tangent of a line drawn at the lowest point of the parabola. If the parabolic reflector is stationary, how can transmitted waves/particles go in any direction but straight up in that perpendiculr direction? If you move the focal point as you say they do, then the antenna does not finction as parabola anymore and gain should drop drastically, agree? I am afraid I must be missing something and request your technical advice. Thanks. |
Modeling Hygain element clamps
I am running the numbers on several 10 meter OWA 6 element antennas
with boom lengths of 24 to 26 ft. Tools on hand are "Yagi Analyzer", "Yagi for Windows" by Dean Straw, and the spreadsheets by W6NL. Several designs look promising, but I've gotten myself confused about how to correctly model the clamps. The official Hygain YO files from Roger Cox are not consistant as to equivalent diameter or length in comparing the 203BA, 204BA, and the 205CA. "What's the problem?" you say. Well, I'd like to use the inboard sections of some 204BA elements for the driven element and the first, close-spaced director. An email to ARRL Technical Services was not enlightening, and re-reading Jim Lawson's and Dave Leeson's works did not give me that warm, confidant feeling that I'd like. Anyone care to enlighten me with actual numbers, or websites?? Gud Lk in the contest! Mike W5CHR Memphis Tenn |
Light,Lazers and HF
On Thu, 11 Sep 2008 16:14:56 -0700 (PDT), Art Unwin
wrote: Try reading the two again. =A0They are identical. =A0The only difference is you don't know the magnitudes of those forces (the length of their vectors) like Jim obviously does. I don't know what you are talking about Two identical statements, one is yours. How is it that you don't understand? The electromagnetic vector for a 1V field imparts 100 Billion times more force than the "weak force." This is why they call it "Weak." The Gravity vector is weaker than that by far. All of this has been known for years. The experiments at CERN are merely adding precision to that number of 100 Billion to say it may actually be 100.015 Billion instead (or perhaps 99.8992 Billion times more force). This goal too, has been reported for years. One day in the future they will know it to that higher precision which will allow them to discern the finer degree of weaker Gravity's disturbance, which, after all, is the whole point of this. No one gives a **** about the Weak force. It is merely the universe's S9+50dB noise from a 5th dimensional neighbor's aquarium heater that is blanking out the S1 DX signal from a graviton. 73's Richard Clark, KB7QHC |
Light,Lazers and HF
"Art Unwin" wrote in message ... My posting is clearly placed within the Earth's boundary so talk of Quarks ,Bosun" Higgs field etc is clearly irrevalent to the subject of radiation unless it is a attempt to bait me or to create confusion about the subject of radiation when its aim should be education and debate. Art Unwin KB9MZ....xg well, art, how dare you think we could be trying to bait you or create more confusion. i hardly think we could possibly create more confusion than you have right now. try to explain these for instance... if it takes that magical mystery particle settling on diamagnetics to create an electromagnetic wave, how does the sun which is all plasma create electromagnetic waves? and if the weak force is so much stronger than gravity, and it interacts with the multitude of these magical mystery particles that spew forth from the sun how come we haven't collapsed into a weak force black hole? it takes lots of mass to create a black hole because gravity is so weak, but if the weak force is stronger than it should collapse us even easier. and if the neutrino's well measured interaction with matter is so weak it must take a huge number of them to be your magical mystery particle so we should really have collapsed under their weak force a long time ago! oh wait, maybe their weak force is what does spin so we are really talking about a spindizzy effect that if captured would allow remote manipulation of matter, i always wondered where Blish came up with that device, maybe you have hit on the secret! come on art, the wx is going to be bad across much of the country here this weekend and we need some good entertainment! |
Light,Lazers and HF
On Sep 12, 6:18*am, "Dave" wrote:
"Art Unwin" wrote in message David, what I have stated is based on known laws and phenomina and started with the recognision that applying a time varying field and radiators to a Gaussian field equates to Maxwell's laws. Right from the start you could not concentrate on proving or disproving that statement ! Until you can determine whether that is correct or not you cannot move forward. As yet, nobody has disproved that statement with counter facts. If you cannot explain that simple fact you surely cannot understand Newtons laws and how the use of such laws provide the presence of eddy current which provides a skin depth of mechanical resistance. I use the term mechanic because I recognise the importance of the four forces in the standard model and the Grand Universal Theory. So until you are able to concentrate and tackle the Gauss and Maxwell connection that I started with there is no hope for you to procede in a scientific matter, and that goes for every body, not just you. Best regards Art |
Modeling Hygain element clamps
On Fri, 12 Sep 2008 01:12:13 -0500, "Mike Lucas"
wrote: "What's the problem?" you say. Well, I'd like to use the inboard sections of some 204BA elements for the driven element and the first, close-spaced director. Hi Mike, I would say "have at it," but what has this got to do with clamps? They cannot present any perturbation to the calculations that wouldn't be lost in the fourth right most digit after the decimal point. Even more un-compelling, modeling probably wouldn't get you any closer to reality than the second right most digit after the decimal point. There are too many confounding properties of earth, nearby objects, and the usual variability in materials and construction to imagine you are going to both model and build one right out of the box, so to speak. On the other hand, actually setting your mind to it and doing it is merely a matter of planning and performance right down to the size of the clamp nuts. This is nothing more than a geometrical description using wire sections of various diameters. The clamp is a half turn of a loop of a certain wire diameter, and the nut is merely a wider wire short section along the straight part of that half loop. Getting it to wrap around an even thicker wire (the boom), and pierce thick wires (the elements) will be a trick, and you will soon discover that you have violated at least one rule of the MANA engine (about proximity of, or overlapping segments). Myself, I would simply make the boom of a series of sections, where the clamp area has a slightly greater diameter. This exercise is useful to do once for the drill. You get to learn what counts and what does not, and then keep only those lessons that actually offer something that lifts above the background noise of mathematical error. 73's Richard Clark, KB7QHC |
Modeling Hygain element clamps
"Richard Clark" wrote: Hi Mike, I would say "have at it," but what has this got to do with clamps? Richard: Tnx for the post- I enjoy slogging through the math to 4 places, but then I usually round off to the nearest 1/16th when building something. My brain had become numb from particals (sic) with spin, dripping from tilted elements. I decided to restart a construction project, just on the odd chance that I'll get it finished and on the tower before (if) the next Solar Cycle happens. So why not some poetry or at least free verse next time??? Mike W5CHR Memphis Tenn |
Light,Lazers and HF
"Art Unwin" wrote in message ... On Sep 12, 6:18 am, "Dave" wrote: "Art Unwin" wrote in message David, what I have stated is based on known laws and phenomina and started with the recognision that applying a time varying field and radiators to a Gaussian field equates to Maxwell's laws. Right from the start you could not concentrate on proving or disproving that statement ! around and around we go... i quoted the required passages from jackson and ramo/whinnery/vanduzer to show that adding time to gauss'es law was incorrect. the law is time independent, meaning it does not require a time term, it applies for all time instantaneously and it is properly included in maxwell's equations as is. your addition of 't' is not necessary. proof is not necessary, it is by definition and intuitively obvious to anyone with the proper background. |
Modeling Hygain element clamps
I have never built a yagi using Hygain elements, but I have built some 6 element OWA's like you want to build. The effect of the clamps will be larger than "4th digit", probably a couple of inches at 28 MHz. But you can ssume to a very good approximation the clamp will just shift the resonant freq of those elements by a certain amount. When I built my OWA's I used DX engineering insulated element mounts. With these, the SWR curve of the real antenna matched the tapered NEC2 model perfectly. I didn't even need to adjust the length of the driven element. If you were using a Hygain element for only the driven element, I would just allow for a few inches of adjustment + or - (hose clamp on last segment), and just adjust the tip length of the final antenna to get the correct SWR curve. If you want to use Hygain elements for Dr and 1st Dir, just do the same, but adjust the lengths of both Dr and 1stDir by the same amount. In the OWA design changing the length of the Dr and 1st Dir is mostly going to affect the matching of the antenna. Tor N4OGW |
Modeling Hygain element clamps
On Fri, 12 Sep 2008 11:33:02 -0500, "Mike Lucas"
wrote: Richard: Tnx for the post- I enjoy slogging through the math to 4 places, An occupation that pleases me too. So why not some poetry or at least free verse next time??? Sorry Mike, Tilting untennas is suggestive of the crusades of the Man of La Mancha and particals (sic) with spin remind me of Singing in the Rain - derivative humor at best here, which is improved by decanting only for the ranting author. Examples abound. However, you can rest assured that using a couple of three syllable words in a sentence is bound to be hooted at as being lifted from Shakespeare, or undecipherable trappings of a foreign language. The hayseed mentality is fairly distributed across the globe but we sure get a unique crop cultivated here. However, as I plunge into your suggestion, one quote comes to mind from Herman Melville's "White Jacket": "It is often observable, that, in vessels of all kinds, the men who talk the most sailor lingo are the least sailor-like in reality. You may sometimes hear even marines jerk out more salt phrases than the Captain of the Forecastle himself. On the other hand, when not actively engaged in his vocation, you would take the best specimen of a seaman for a landsman. When you see a fellow yawning about the docks like a homeward-bound Indiaman, a long Commodore's pennant of black ribbon flying from his mast- head, and fetching up at a grog-shop with a slew of his hull, as if an Admiral were coming alongside a three-decker in his barge; you may put that man down for what man-of-war's-men call a 'damn-my-eyes-tar', that is, a humbug. And many damn-my-eyes hum-bugs there are in this man-of-war world of ours." 73's Richard Clark, KB7QHC |
Light,Lazers and HF
On Sep 12, 11:39*am, "Dave" wrote:
"Art Unwin" wrote in message ... On Sep 12, 6:18 am, "Dave" wrote: "Art Unwin" wrote in message David, what I have stated is based on known laws and phenomina and started with the recognision that applying a time varying field and radiators to a Gaussian field equates to Maxwell's laws. Right from the start you could not concentrate on proving or disproving that statement ! around and around we go... i quoted the required passages from jackson and ramo/whinnery/vanduzer to show that adding time to gauss'es law was incorrect. *the law is time independent, meaning it does not require a time term, it applies for all time instantaneously and it is properly included in maxwell's equations as is. *your addition of *'t' is not necessary. *proof is not necessary, it is by definition and intuitively obvious to anyone with the proper background. Oh David I extended it to make it dynamic by adding a time varying current where it duplicates Maxwells law Find a ham who is conversant with physics and mathematics bring him forward on your behalf for debate. Tell him what you want debated say, what is stated above. Do that and you will do a service for ham radio. Warn him that the question as to whether a static field can be transformed to a dynamic field quoting any book that says you can't. He will then refuse to appear. End of story. Art...is it still raining? Are you still all wet? |
Light,Lazers and HF
"Art Unwin" wrote in message ... On Sep 12, 11:39 am, "Dave" wrote: Oh David I extended it to make it dynamic by adding a time varying current where it duplicates Maxwells law so you had to extend a set of equations that you say is giving proper results as they were written oh so long ago and have been implemented in all sorts of antenna modeling software that you say works just fine... so what did your extension do? if the software works as is without your changes to the equations then how are your changes necessary? what does your change to them predict that isn't already in there?? since you didn't write your own software, but are fond of quoting results of whatever you use, then obviously your change wasn't necessary and yet you rely on it... very strange... and no, its still raining and should be raining all weekend... so keep ranting... i still want to know about the neutrinos and how they settle on plasmas that are decidedly not diamagnetic and cause them to radiate. |
Light,Lazers and HF
On Sep 12, 7:08*pm, "Dave" wrote:
"Art Unwin" wrote in message ... On Sep 12, 11:39 am, "Dave" wrote: Oh David I extended it to make it dynamic by adding a time varying current *where it duplicates Maxwells law so you had to extend a set of equations that you say is giving proper results as they were written oh so long ago and have been implemented in all sorts of antenna modeling software that you say works just fine... so what did your extension do? *if the software works as is without your changes to the equations then how are your changes necessary? *what does your change to them predict that isn't already in there?? *since you didn't write your own software, but are fond of quoting results of whatever you use, then obviously your change wasn't necessary and yet you rely on it... very strange... and no, its still raining and should be raining all weekend... so keep ranting... i still want to know about the neutrinos and how they settle on plasmas that are decidedly not diamagnetic and cause them to radiate. IF YOU DO NOT PRE GUIDE IT TO A PLANAR DESIGN WHICH DOES NOT INCLUDE THE WEAK FORCE IT WILL SUPPLY A BETTER RADIATOR BY ADDING THE WEAK FORCE TO SUPPLY REQUIREMENTS ASKED OF IT PER MAXWELLS LAWS AND NOT BY YAGI APPROACH. I.E ASK FOR MAX GAIN AND THE PROGRAM CHOOSES. ART |
Light,Lazers and HF
On Sep 12, 12:59*am, Mark Cudworth
wrote: wrote: That is interesting. I thought the PR dish was parabolic. As a parabola, the reflected waves (or particles if you will) of a transmitter at focal point can only traverse in one direction, that is, in a direction parallel to the tangent of a line drawn at the lowest point of the parabola. If the parabolic reflector is stationary, how can transmitted waves/particles go in any direction but straight up in that perpendiculr direction? If you move the focal point as you say they do, then the antenna does not finction as parabola anymore and gain should drop drastically, agree? I am afraid I must be missing something and request your technical advice. Thanks. The Arecibo radio telescope has a spherical reflector, not parabolic. This is mentioned on the official web page: * *http://www.naic.edu/public/the_telescope.htm It also gives details on how the telescope operates. -- Mark Cudworth Thank you Mark. It truly is spherical. |
Light,Lazers and HF
On Sep 12, 10:35*am, Art Unwin wrote:
On Sep 12, 6:18*am, "Dave" wrote: "Art Unwin" wrote in message David, what I have stated is based on known laws and phenomina and started with the recognision that applying a time varying field and radiators to a Gaussian field equates to Maxwell's laws. Right from the start you could not concentrate on proving or disproving that statement ! *Until you can determine whether that is correct or not you cannot move forward. As yet, nobody has disproved that statement with counter facts. If you cannot explain that simple fact you surely cannot understand Newtons laws and how the use of such laws provide the presence of eddy current which provides a skin depth of mechanical resistance. I use the term mechanic *because I recognise the importance of the four forces in the standard model and the Grand Universal Theory. So until you are able to concentrate and tackle the Gauss and Maxwell connection that I started with there is no hope for you to procede in a scientific matter, and that goes for every body, not just you. Best regards Art To it would be nice if physics was so tidy that there could be shown a neat relationship of the 4 forces, thus the birth of a new Grand Unification Theory. Einstein would have liked to find the unifying factor but he dies before he could accomplish that. He never claimed that there had to be a iuifier, only that physics was of such an orderly nature that it would seem consistent that there should be a unification. Art is acting on the assumption that there MUST be a unifier. The CERN scientists postulate that some particle such as a theoretical higgs boson could be discovered and observed as the "God particle" that imparts matter to other particles which creates mass, matter being pervasive in the universe but mostly in its invisible dark form. From that they say that we could begin to study the relationship of this higgs boson to the other seeminly unrelated forces and find a grand unifier. To me, the concept of a unifier is NOT something that necessarily has to exist. Maybe there is no unifier and in fact, the student of quantum physics does not see physics as being completely orderly as a student of astrophysics sees it. At the quantum level, the universe is highly random and probabilistic. Any forces we have identified at that level, and future forces we discover, do not have to be unified by any theory; that is not the way I see things either. I see no reason for scientisits to chase after this holy grail (other than by doing so at low cost and in their spare time so as not to waster resources) and I see the likelihood of anyone finding it at 10% at best. There is no observation or calculation that states a unifier must exist, For all the good that will result in the future from the CERN accelerator, looking for a unfier based on new studies of a "higgs boson" (God) particle is a Hail Mary pass that in all likelihood will not succeed. Let's not be dissapointed when it doesn't. For HF antennas, most is already known which needs to be known by application of known EM principles, the study of which has infinitely less likelihood of pointing to a grand unifier as Art repeatedly attempts in these postings. However, he is doing it in his spare time and at no cost to society thus fulfilling what I think is the amount of resources should be expended in finding the grand unifier. |
Modeling Hygain element clamps
wrote When I built my OWA's I used DX engineering insulated element mounts. With these, the SWR curve of the real antenna matched the tapered NEC2 model perfectly. I didn't even need to adjust the length of the driven element. Tor: Thanks for the reply. I've used home-brew plates and u-bolts for a couple of 3 and 4 element 10M antennas, but all were grounded. The gamma match that was spit out by the YA program worked as calculated, and within the limits of the equipment, the measured VSWR curves matched the model. While the subject line said "Hygain element clamps", I also have a box full of Wilson element clamps, both are close in appearance, but the Wilson clamps are about 15-20% larger than the Hygain of the same element size. First runs on an OWA for 10M used 3/4, 5/8, and 1/2 in. tubing, with a bushing in the element clamp to bring it down to 3/4 size. I was looking for flat gain and F/B curves, close to 50 Ohm feed, and use on-hand parts. I came up with a couple of models that looked promising, but I'm now looking at using 1-1/4 to 7/8 taper elements for the driven and first director. Since my optimizer is me, I haven't run enough samples to tell if that will show any improvement. What I have seen is that if a design is poor, a small change in taper schedule, element length or element spacing will make a noticeable change in the model characteristics, usually bad. Plans are for a single 10M OWA here in Memphis, to be followed by a 3-high stack at the retirement Ponderosa. I have also looked at scaling up to 20M, where a 3 inch boom prevents using the clamp style mounts. Sooo, thanks for the post, and I'll see you on the bands. Mike W5CHR Memphis Tenn |
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