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art wrote:
www.newswise.com/articles/view/532935 Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made A$$'es out of all the "experts" and continues to do so ... sometimes there is real justice. Regards, JS |
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On 9 Oct, 19:35, John Smith wrote:
art wrote: www.newswise.com/articles/view/532935 Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made A$$'es out of all the "experts" and continues to do so ... sometimes there is real justice. Regards, JS Yup, the experts were not experts after all just phony's. Ofcourse we now have to wait for comments like " I knew that all the time", "I have been using that method for years", "that was invented by Mantovani a hundred yeard ago but he just didn't get around to printing it" Art |
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art wrote:
... a hundred yeard ago but he just didn't get around to printing it" Art Art: You forgot: "Although the Navy meant well, it's test data was in error!" :-) Regards, JS |
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On 10 Oct, 09:04, John Smith wrote:
art wrote: ... a hundred yeard ago but he just didn't get around to printing it" Art Art: You forgot: "Although the Navy meant well, it's test data was in error!" :-) Regards, JS What was the error? The antenna feed line is part of the antenna system is it not? If it radiates then what is the problem? Art Art |
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art wrote:
On 9 Oct, 19:35, John Smith wrote: art wrote: www.newswise.com/articles/view/532935 Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made A$$'es out of all the "experts" and continues to do so ... sometimes there is real justice. Regards, JS Yup, the experts were not experts after all just phony's. Ofcourse we now have to wait for comments like " I knew that all the time", "I have been using that method for years", "that was invented by Mantovani a hundred yeard ago but he just didn't get around to printing it" Art The patent, US 7187335, is a real hoot. I especially like the part where he describes doubling the bandwidth by adding a parasitic winding intertwined with the base coil helix. Do you suppose his antenna is in equilibrium? Could proper application of Artsian-Gaussian theory improve it even more? :D 73, Gene W4SZ |
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On 10 Oct, 10:47, Gene Fuller wrote:
art wrote: On 9 Oct, 19:35, John Smith wrote: art wrote: www.newswise.com/articles/view/532935 Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made A$$'es out of all the "experts" and continues to do so ... sometimes there is real justice. Regards, JS Yup, the experts were not experts after all just phony's. Ofcourse we now have to wait for comments like " I knew that all the time", "I have been using that method for years", "that was invented by Mantovani a hundred yeard ago but he just didn't get around to printing it" Art The patent, US 7187335, is a real hoot. I especially like the part where snip Do you suppose his antenna is in equilibrium? Could proper application of Artsian-Gaussian theory improve it even more? :D 73, Gene W4SZ- Hide quoted text - - Show quoted text - Gene, you are just showing your ignorance of physics. What is it about the word "equilibrium" that you can't understand? How on earth can you say you are educated in physics? How is it that you do not have an understanding of Gauss? Or are you trying to be funny with the word "Artisian-Gaussian" like the rest of your fellow school boys? What manner of man are you trying to project of yourself to other readers of this group, a comedian or an ignoramous or somebody with senior moments in continuos series? You never seem to have anything to say that is informative so why the need to draw attention to yourself. What is missing in your life such that you have to mimic a fool that want's to be funny in the absence of a education of any sort? Back to the Vincent antenna, he has designed an antenna that is shorter than that known before. You didn't come up with it he did. He has a patent based on his claims and not for the introductory writing.An engineer in automobiles has shown interest in it where you have never gained outside interests in any thing you have done in your life time. The input impedance is an advantage over similar antennas and at the same time not requiring a ground plain without being a problem to the transmitter. He is also radiating well in comparison to the height of antenna and the radiating system has the appearance of being efficient. Vincent has come up with something new and because of the 'not invented in my backyard' you want to diminish his achievements. But you can't diminish his achievments without providing an engineering analysis and for that you do not have the necessary education. Maybe it is better that you continue to mimic a fool that wants to be funny but better to become a succes at that at home before showing off your skills in public even tho you are getting laughter, not with you but at you. Art Art |
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Gene Fuller wrote:
... The patent, US 7187335, is a real hoot. I especially like the part where he describes doubling the bandwidth by adding a parasitic winding intertwined with the base coil helix. Do you suppose his antenna is in equilibrium? Could proper application of Artsian-Gaussian theory improve it even more? :D 73, Gene W4SZ What? You don't see cutting the capacitance between winding turns as causing some measurable effect which in turn affects a property of the antenna proper? Thicker conductor(s) usually means a measurable gain in bandwith, with a parasitic element in such close proximity to the major element, a gain in bandwidth is not that difficult to propose and attempt to prove/disprove. Regards, JS |
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art wrote:
... What was the error? The antenna feed line is part of the antenna system is it not? If it radiates then what is the problem? Art Art I have a 1/4 wave counterpoise available to the 1/2 DLM I am using. However, I have a high value choke to ward off radiation from the coax ... Regards, JS |
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On 10 Oct, 20:51, John Smith wrote:
art wrote: ... What was the error? The antenna feed line is part of the antenna system is it not? If it radiates then what is the problem? Art Art I have a 1/4 wave counterpoise available to the 1/2 DLM I am using. However, I have a high value choke to ward off radiation from the coax ... Regards, JS What is wrong with the coax radiating? Art |
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art wrote:
... What is wrong with the coax radiating? Art Personally, my major complaint is in the "lack of control" over antenna performance/operating characteristics. For instance, with the feed-line allowed to radiate, movement/placement of the coax tends to affect SWR, radiation pattern(s), etc.--sometimes dramatically. This is very undesirable, at least to me, in a mobile/field-day/camping/etc. antenna ... Regards, JS |
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John Smith wrote:
Gene Fuller wrote: ... The patent, US 7187335, is a real hoot. I especially like the part where he describes doubling the bandwidth by adding a parasitic winding intertwined with the base coil helix. Do you suppose his antenna is in equilibrium? Could proper application of Artsian-Gaussian theory improve it even more? :D 73, Gene W4SZ What? You don't see cutting the capacitance between winding turns as causing some measurable effect which in turn affects a property of the antenna proper? Thicker conductor(s) usually means a measurable gain in bandwith, with a parasitic element in such close proximity to the major element, a gain in bandwidth is not that difficult to propose and attempt to prove/disprove. Regards, JS John, The effects you mention may have some impact on bandwidth, but they don't double it. And the capacitance probably increases, not decreases. Placing an extra conductor between two capacitor plates increases the capacitance. At the same time placing a grounded shield between two capacitor plates reduces or eliminates the coupling between the original plates. It is not clear to me which effect would dominate in this case. In either case it is unlikely to be very important. Lots of people understand how to make an antenna broadband; simply add resistance. This is not always "bad". It is merely a choice. Just for grins I did a little EZNEC experiment. I started with a base loaded monopole that used a generated helix as the loading coil. I adjusted and resonated the system to SWR = 1 and took a look at the bandwidth. I arbitrarily took SWR = 2 as the bandwidth limits. I then added a parasitic winding between the turns of the helix. This winding was not connected to anything. I reran the simulations. What I found was interesting, but not surprising. When the wires were treated as lossless, there was virtually no difference in bandwidth or any other parameter. The parasitic winding had essentially no impact. When I changed the wires to copper, the bandwidth increased in both cases. However, in the case with the parasitic winding the new bandwidth was 2.5 times as large as the case without the extra winding. The resonant input impedance was also about 2.5 times larger. There is only one plausible explanation for this observation. The parasitic winding adds loss to the antenna system. I won't claim this is "bad". Depends on the characteristics desired. The bottom line is that there is no wondrous invention here. Either Vincent knew about this effect and chose to ignore it, or he did not understand what was happening. The capacitance explanation is just baloney. 73, Gene W4SZ |
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Gene Fuller wrote:
... 73, Gene W4SZ Well, OK. Post your EZNEC modeling mockup of the antenna and we'll check it out ... :-) JS |
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Jimmie D wrote:
... Hi Gene, From the data posted by Vincent I dont think he is trying to be a fraud. Maybe he is just unaware that the data he is discovering about short antennas is about 70 or 80 years old. That would be giving him the benifit of the doubt. Jimmie Post that 70-80 year old EZNEC mockup you are familiar with and we'll check it out ... JS |
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Gene Fuller wrote:
. . . What I found was interesting, but not surprising. When the wires were treated as lossless, there was virtually no difference in bandwidth or any other parameter. The parasitic winding had essentially no impact. When I changed the wires to copper, the bandwidth increased in both cases. However, in the case with the parasitic winding the new bandwidth was 2.5 times as large as the case without the extra winding. The resonant input impedance was also about 2.5 times larger. There is only one plausible explanation for this observation. The parasitic winding adds loss to the antenna system. I won't claim this is "bad". Depends on the characteristics desired. You can easily verify this by noting the change in gain as the extra winding is added and deleted. You should also see a corresponding change in feedpoint resistance, assuming that the extra winding doesn't change the current distribution. A couple of additional interesting experiments would be: 1. Increase the loss of the coil in a model without the extra winding until the gain is the same as the model with copper loss and no extra winding. Then see how the bandwidth compares to the original model with extra winding. 2. Instead of increasing the loss of the coil, add a resistor to the base of the copper loss non-extra winding antenna and adjust it so the gain is the same as for the model with copper loss and extra winding. How does the bandwidth compare to the original model with the extra winding? The bottom line is that there is no wondrous invention here. Either Vincent knew about this effect and chose to ignore it, or he did not understand what was happening. The capacitance explanation is just baloney. I'm afraid that's probably true. With antennas, you can choose any two of efficient, and broadband, and electrically small. This antenna claims all three, so I'm very skeptical. Roy Lewallen, W7EL |
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John Smith wrote: Jimmie D wrote: ... Hi Gene, From the data posted by Vincent I dont think he is trying to be a fraud. Maybe he is just unaware that the data he is discovering about short antennas is about 70 or 80 years old. That would be giving him the benifit of the doubt. Jimmie Post that 70-80 year old EZNEC mockup you are familiar with and we'll check it out ... JS I dont have EZNEC, But I will trust you if you care to model a 1/4wl monopole and compare it to an 1/8wl monople operating against a perfect counterpoise. Fine enginneer that Art is he should have no trouble in calculating field intensity at a receiving antenna 1 mile away. I have total respect for the integrity of your work as long as you show your math. Jimmie |
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JIMMIE wrote:
... I dont have EZNEC, But I will trust you if you care to model a 1/4wl monopole and compare it to an 1/8wl monople operating against a perfect counterpoise. Fine enginneer that Art is he should have no trouble in calculating field intensity at a receiving antenna 1 mile away. I have total respect for the integrity of your work as long as you show your math. Jimmie No. We are talking about a small antenna ~25% of full 1/4 wave length which performs as well or outperforms its full length 1/4 wave version. We are talking about a 1/2 wave antenna which is only 20-30% the length of its full length 1/2 wave version which performs as well or even out performs its' full 1/2 wave length ... Show me an EZNEC model of what the Navy tested for Mr. Vincent--indeed, show me where anyone before Mr. Vincent was able to demonstrate a working model capable of the above characteristics? JS |
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On 11 Oct, 11:12, "Jimmie D" wrote:
"Gene Fuller" wrote in message ... art wrote: On 9 Oct, 19:35, John Smith wrote: art wrote: www.newswise.com/articles/view/532935 Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made A$$'es out of all the "experts" and continues to do so ... sometimes there is real justice. Regards, JS Yup, the experts were not experts after all just phony's. Ofcourse we now have to wait for comments like " I knew that all the time", "I have been using that method for years", "that was invented by Mantovani a hundred yeard ago but he just didn't get around to printing it" Art The patent, US 7187335, is a real hoot. I especially like the part where he describes doubling the bandwidth by adding a parasitic winding intertwined with the base coil helix. Do you suppose his antenna is in equilibrium? Could proper application of Artsian-Gaussian theory improve it even more? :D 73, Gene W4SZ Hi Gene, From the data posted by Vincent I dont think he is trying to be a fraud. Maybe he is just unaware that the data he is discovering about short antennas is about 70 or 80 years old. That would be giving him the benifit of the doubt. Jimmie- Hide quoted text - - Show quoted text - Well said Art |
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On 11 Oct, 15:45, John Smith wrote:
JIMMIE wrote: ... I dont have EZNEC, But I will trust you if you care to model a 1/4wl monopole and compare it to an 1/8wl monople operating against a perfect counterpoise. Fine enginneer that Art is he should have no trouble in calculating field intensity at a receiving antenna 1 mile away. I have total respect for the integrity of your work as long as you show your math. Jimmie No. We are talking about a small antenna ~25% of full 1/4 wave length which performs as well or outperforms its full length 1/4 wave version. We are talking about a 1/2 wave antenna which is only 20-30% the length of its full length 1/2 wave version which performs as well or even out performs its' full 1/2 wave length ... Show me an EZNEC model of what the Navy tested for Mr. Vincent--indeed, show me where anyone before Mr. Vincent was able to demonstrate a working model capable of the above characteristics? JS Gentlemen, Vincent did produce a shorter antenna than was known before with a 50 ohm impedance feed which is a huge advantage for designers that want to hide, encapsulate or what have you for a small antenna in this wifi age and nobody can take that away from him even tho his knoweledge of antennas is limited. If he understood Gaussian law then he could have made the Gaussian antenna which requires an element in equilibrium which means a FULL WAVELENGTH. I know you dislike the meaning of the term equilibrium b ut here it is indispesable. Even without the knoweledge of Gauss he came very close to Gauss or the biggest discovery of the century If one winds a half wave length in a clockwise direction starting at the top going down and then repeating with another halfwave length but winding it in a counterclockwise direction( preferably winding both wires at the same time) and then joining together the two wires at the top he would then have a copy of my Gaussian antenna. Note that the errant current flow that Vincent has on the feed line now has a path to travel where it can radiate and still have a resistive match at the feed points. This by the way is bidirectional Now one can again expand the Gaussian principle by making the antenna height less than the wound diameter to make a circular polarity radiating antenna. Also note that Gauss's work then leads to a maximum gain when the antenna is at right angles to the earth but knowing that a full summation of all vectors on the radiator is around 10 to 12 degrees from the radiator axis the radiator when tilted will maximise a particular polarity alone. You can deride Vincents achievement as something useless but the Gaussian antenna is here,it is real and the mathematics regarding the extension of the Gaussian aproach gives an insight as to how radiation is really created which has been the goal of scientists for more than a hundred years. And the experts on this newsgroup who were told of this first derided it also. Make a sample of a single wound antenna and then make a mirror immage of same and joining at the top. Then study it to determine if the windings of an inductor represents a portionof the resonant length........... remember that augument, maybe you should revisit it! Yuri you can provide your normal account as to how antennas work in a contrary fashion. And yes Roy you can repeat your phrase of "I don't understand it{" As for others with computor programs you can alsomodel it for yourselves and then curse your computor. Regards Art KB9MZ......XG |
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On 11 Oct, 13:47, JIMMIE wrote:
John Smith wrote: Jimmie D wrote: ... Hi Gene, From the data posted by Vincent I dont think he is trying to be a fraud. Maybe he is just unaware that the data he is discovering about short antennas is about 70 or 80 years old. That would be giving him the benifit of the doubt. Jimmie Post that 70-80 year old EZNEC mockup you are familiar with and we'll check it out ... JS I dont have EZNEC, But I will trust you if you care to model a 1/4wl monopole and compare it to an 1/8wl monople operating against a perfect counterpoise. Fine enginneer that Art is he should have no trouble in calculating field intensity at a receiving antenna 1 mile away. I have total respect for the integrity of your work as long as you show your math. Jimmie- Hide quoted text - - Show quoted text - Jimmy, I don't have eznec either but I can still experiment the old fashioned way. As for a recieve antenna by next experiment gyrates in that direction. Having proved that the inductance and capacitance of a radiator are acting as energy sinks that explode when the terminal are closed I am now going to place a gaussian antenna between two 8 by 4 sheets of aluminium sheeting which I purchased.I want to act as a capacitor from which my antenna will draw energy from to provide a larger aparture for my antenna for receiving. Question remains as to how the circuit for the large capacitor turns out and what amount of energy it will absorb that I can steal from it to aid my Gaussian antenna.I suppose I could resonate the capacitor at the same frequency that I want to receive!!!!! It can all be a failure but it will be one less to make in the future. Art |
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On Oct 11, 6:45 pm, John Smith wrote:
JIMMIE wrote: ... I dont have EZNEC, But I will trust you if you care to model a 1/4wl monopole and compare it to an 1/8wl monople operating against a perfect counterpoise. Fine enginneer that Art is he should have no trouble in calculating field intensity at a receiving antenna 1 mile away. I have total respect for the integrity of your work as long as you show your math. Jimmie No. We are talking about a small antenna ~25% of full 1/4 wave length which performs as well or outperforms its full length 1/4 wave version. We are talking about a 1/2 wave antenna which is only 20-30% the length of its full length 1/2 wave version which performs as well or even out performs its' full 1/2 wave length ... Show me an EZNEC model of what the Navy tested for Mr. Vincent--indeed, show me where anyone before Mr. Vincent was able to demonstrate a working model capable of the above characteristics? JS http://www.fi.uba.ar/materias/6654/d...FMFAntenna.pdf Probably more than you ever wanted to know about short antennas. Jimmie |
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On 11 Oct, 18:58, JIMMIE wrote:
On Oct 11, 6:45 pm, John Smith wrote: JIMMIE wrote: ... I dont have EZNEC, But I will trust you if you care to model a 1/4wl monopole and compare it to an 1/8wl monople operating against a perfect counterpoise. Fine enginneer that Art is he should have no trouble in calculating field intensity at a receiving antenna 1 mile away. I have total respect for the integrity of your work as long as you show your math. Jimmie No. We are talking about a small antenna ~25% of full 1/4 wave length which performs as well or outperforms its full length 1/4 wave version. We are talking about a 1/2 wave antenna which is only 20-30% the length of its full length 1/2 wave version which performs as well or even out performs its' full 1/2 wave length ... Show me an EZNEC model of what the Navy tested for Mr. Vincent--indeed, show me where anyone before Mr. Vincent was able to demonstrate a working model capable of the above characteristics? JS http://www.fi.uba.ar/materias/6654/d...FMFAntenna.pdf Probably more than you ever wanted to know about short antennas. Jimmie- Hide quoted text - - Show quoted text - Now a bunch of erronious information He states for short antennas a good ground field is paramount which is false. It is correct for a fractional wavelength antenna but not for a short antenna. Then he goes on to relate a top hat with efficiency so the question is does the top hat make radiation per unit length the same terminology as efficiency since the top hat does not increase height? Basically, if you have a fractional wavelength antenna then a ground plane is paramount to provide a low resistance to ground (power loss)for the the ANTENNA circuit. If a low resistance path to ground is not there then the system is closed by the outside of the feed sheathing to transmitter ground which closes the ANTENNA system providing combination radiation as well as system loss. I say again, one must have equilibrium for maximum efficiency and that requires a full wave length radiator and at the same time holding to the LC ratio for that length. These are cardinal rules as shown by Gauss. Regards Art KB9MZ |
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On Oct 11, 4:25 pm, Roy Lewallen wrote:
Gene Fuller wrote: . . . What I found was interesting, but not surprising. When the wires were treated as lossless, there was virtually no difference in bandwidth or any other parameter. The parasitic winding had essentially no impact. When I changed the wires to copper, the bandwidth increased in both cases. However, in the case with the parasitic winding the new bandwidth was 2.5 times as large as the case without the extra winding. The resonant input impedance was also about 2.5 times larger. There is only one plausible explanation for this observation. The parasitic winding adds loss to the antenna system. I won't claim this is "bad". Depends on the characteristics desired. You can easily verify this by noting the change in gain as the extra winding is added and deleted. You should also see a corresponding change in feedpoint resistance, assuming that the extra winding doesn't change the current distribution. A couple of additional interesting experiments would be: 1. Increase the loss of the coil in a model without the extra winding until the gain is the same as the model with copper loss and no extra winding. Then see how the bandwidth compares to the original model with extra winding. 2. Instead of increasing the loss of the coil, add a resistor to the base of the copper loss non-extra winding antenna and adjust it so the gain is the same as for the model with copper loss and extra winding. How does the bandwidth compare to the original model with the extra winding? The bottom line is that there is no wondrous invention here. Either Vincent knew about this effect and chose to ignore it, or he did not understand what was happening. The capacitance explanation is just baloney. I'm afraid that's probably true. With antennas, you can choose any two of efficient, and broadband, and electrically small. This antenna claims all three, so I'm very skeptical. Roy Lewallen, W7EL- Hide quoted text - - Show quoted text - Maybe it not the wire but the insulation on the wire, A little dielectric heating would surely make it more broadbanded. Jimmie |
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"art" wrote in message oups.com... If he understood Gaussian law then he could have made the Gaussian antenna which requires an element in equilibrium which means a FULL WAVELENGTH. I know you dislike the meaning of the term equilibrium b ut here it is indispesable. you contradict yourself now... you told us before that you used half wavelength elements for you 'gaussian' antenna???? Even without the knoweledge of Gauss he came very close to Gauss or the biggest discovery of the century If one winds a half wave length in a clockwise direction starting at the top going down and then repeating with another halfwave length but winding it in a counterclockwise direction( preferably winding both wires at the same time) and then joining together the two wires at the top he would then have a copy of my Gaussian antenna. Another contradiction. earlier you have said that the 'gaussian' elements were simple straight halfwave elements???? and ONE MORE TIME.... define 'equilibrium'. write the equations. just what is in 'equilibrium' with what?? |
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On 13 Oct, 03:55, "Dave" wrote:
"art" wrote in message oups.com... If he understood Gaussian law then he could have made the Gaussian antenna which requires an element in equilibrium which means a FULL WAVELENGTH. I know you dislike the meaning of the term equilibrium b ut here it is indispesable. you contradict yourself now... you told us before that you used half wavelength elements for you 'gaussian' antenna???? Hi David, back to your old tricks again eh? If you go up a halfwave length and then come down a halfwaveleng you then have 2 x 1/2 so you don't have a half wave length anymore. Watch the childrens hour on TV for the answer Even without the knoweledge of Gauss he came very close to Gauss or the biggest discovery of the century If one winds a half wave length in a clockwise direction starting at the top going down and then repeating with another halfwave length but winding it in a counterclockwise direction( preferably winding both wires at the same time) and then joining together the two wires at the top he would then have a copy of my Gaussian antenna. Another contradiction. earlier you have said that the 'gaussian' elements were simple straight halfwave elements???? You have just got to watch childrens hour to get up to speed for your mathematics, new math that is. A gaussian antenna can be any shape, size or configuration as long as it is in a state of equilibrium and ONE MORE TIME.... define 'equilibrium'. write the equations. just what is in 'equilibrium' with what?? No David I am not going to go thru all that again,get yourself a physics book or Google around Art |
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"Dave" wrote
and ONE MORE TIME.... define 'equilibrium'. write the equations. just what is in 'equilibrium' with what?? __________ Art posted his definition in this thread on Oct 11. But no math to support it. \\ If he understood Gaussian law then he could have made the Gaussian antenna which requires an element in equilibrium which means a FULLWAVELENGTH. I know you dislike the meaning of the term equilibrium but here it is indispesable. // What I get from his comments is that Art believes fractional wavelength radiators are inefficient because they are not in equilibrium, ie, they are not a full wave length and therefore don't act like a tank circuit (he says) -- which he believes is necessary for efficient radiation. I've sent Art several emails with NEC results and math-based discussion showing that a 1/4-wave monopole working against a 2-ohm r-f ground plane radiates about 95% of the power applied by a matched source between it base feedpoint and r-f ground. This is the configuration used by virtually all commercial AM broadcast stations, and its very high system radiation efficiency has been proven thousands of times since the earliest days of broadcasting. Of course that is at odds with the beliefs Art continues to post here and elsewhere. In a response to my emails Art seemed to understand, and even thanked me for "sticking with it." But I guess he was not convinced, because he started this thread _after_ our email exchange. Since my discussions with Art I put together a chart showing the groundwave field generated at 1 km by several, fractional wavelength monopoles at applied powers from 1-10 kW (see link below). I used a perfect ground plane in preparing the chart, but the values would be only slightly less with a 2-ohm r-f ground. ART: Note that the 1 kW field for the 1/4-wave monopole is exactly the peak field of a 1/2-wave dipole in free space (about 313 mV/m). Taller monopoles generate more groundwave field, given the same applied power and r-f ground, because their radiation patterns have more gain in the horizontal plane and less gain in other directions -- not because they are more "efficient." All of the monopoles in this chart radiate all of the power applied to them (100% efficient). Also note, Art, that a 1/2-wave monopole and its ground image comprise a full-wave antenna (eg, having your "equilibrium"), yet the 195-degree and 225-degree monopoles produce higher groundwave fields, even though they are NOT by your definition "in equilibrium." http://i62.photobucket.com/albums/h8...Radiator10.gif RF |
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On 13 Oct, 06:28, "Richard Fry" wrote:
"Dave" wrote and ONE MORE TIME.... define 'equilibrium'. write the equations. just what is in 'equilibrium' with what?? __________ Art posted his definition in this thread on Oct 11. But no math to support it. \\ If he understood Gaussian law then he could have made the Gaussian antenna which requires an element in equilibrium which means a FULLWAVELENGTH. I know you dislike the meaning of the term equilibrium but here it is indispesable. // What I get from his comments is that Art believes fractional wavelength radiators are inefficient because they are not in equilibrium, ie, they are not a full wave length and therefore don't act like a tank circuit (he says) -- which he believes is necessary for efficient radiation. I've sent Art several emails with NEC results and math-based discussion showing that a 1/4-wave monopole working against a 2-ohm r-f ground plane radiates about 95% of the power applied by a matched source between it base feedpoint and r-f ground. This is the configuration used by virtually all commercial AM broadcast stations, and its very high system radiation efficiency has been proven thousands of times since the earliest days of broadcasting. Of course that is at odds with the beliefs Art continues to post here and elsewhere. In a response to my emails Art seemed to understand, and even thanked me for "sticking with it." But I guess he was not convinced, because he started this thread _after_ our email exchange. Since my discussions with Art I put together a chart showing the groundwave field generated at 1 km by several, fractional wavelength monopoles at applied powers from 1-10 kW (see link below). I used a perfect ground plane in preparing the chart, but the values would be only slightly less with a 2-ohm r-f ground. ART: Note that the 1 kW field for the 1/4-wave monopole is exactly the peak field of a 1/2-wave dipole in free space (about 313 mV/m). Taller monopoles generate more groundwave field, given the same applied power and r-f ground, because their radiation patterns have more gain in the horizontal plane and less gain in other directions -- not because they are more "efficient." All of the monopoles in this chart radiate all of the power applied to them (100% efficient). Also note, Art, that a 1/2-wave monopole and its ground image comprise a full-wave antenna (eg, having your "equilibrium"), yet the 195-degree and 225-degree monopoles produce higher groundwave fields, even though they are NOT by your definition "in equilibrium." http://i62.photobucket.com/albums/h8...veFieldvsPower... RF When you said if the Gaussian antenna was real it would have been invented long ago or something like that and yet they are still giving out patents and Nobel prizes out for things that are newly discovered I lost interest in your musings. When you added things like an image is real I have to walk away because you are just not on my wavelength. I fed the half wave image and also hooked it up to a receiver and I heard nothing, let me know when you make a contact or maybe I should dig a little bit deeper! Art Art |
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"art" wrote in message ups.com... On 13 Oct, 06:28, "Richard Fry" wrote: "Dave" wrote and ONE MORE TIME.... define 'equilibrium'. write the equations. just what is in 'equilibrium' with what?? __________ Art posted his definition in this thread on Oct 11. But no math to support it. \\ If he understood Gaussian law then he could have made the Gaussian antenna which requires an element in equilibrium which means a FULLWAVELENGTH. I know you dislike the meaning of the term equilibrium but here it is indispesable. // What I get from his comments is that Art believes fractional wavelength radiators are inefficient because they are not in equilibrium, ie, they are not a full wave length and therefore don't act like a tank circuit (he says) -- which he believes is necessary for efficient radiation. I've sent Art several emails with NEC results and math-based discussion showing that a 1/4-wave monopole working against a 2-ohm r-f ground plane radiates about 95% of the power applied by a matched source between it base feedpoint and r-f ground. This is the configuration used by virtually all commercial AM broadcast stations, and its very high system radiation efficiency has been proven thousands of times since the earliest days of broadcasting. Of course that is at odds with the beliefs Art continues to post here and elsewhere. In a response to my emails Art seemed to understand, and even thanked me for "sticking with it." But I guess he was not convinced, because he started this thread _after_ our email exchange. Since my discussions with Art I put together a chart showing the groundwave field generated at 1 km by several, fractional wavelength monopoles at applied powers from 1-10 kW (see link below). I used a perfect ground plane in preparing the chart, but the values would be only slightly less with a 2-ohm r-f ground. ART: Note that the 1 kW field for the 1/4-wave monopole is exactly the peak field of a 1/2-wave dipole in free space (about 313 mV/m). Taller monopoles generate more groundwave field, given the same applied power and r-f ground, because their radiation patterns have more gain in the horizontal plane and less gain in other directions -- not because they are more "efficient." All of the monopoles in this chart radiate all of the power applied to them (100% efficient). Also note, Art, that a 1/2-wave monopole and its ground image comprise a full-wave antenna (eg, having your "equilibrium"), yet the 195-degree and 225-degree monopoles produce higher groundwave fields, even though they are NOT by your definition "in equilibrium." http://i62.photobucket.com/albums/h8...veFieldvsPower... RF When you said if the Gaussian antenna was real it would have been invented long ago or something like that and yet they are still giving out patents and Nobel prizes out for things that are newly discovered I lost interest in your musings. When you added things like an image is real I have to walk away because you are just not on my wavelength. I fed the half wave image and also hooked it up to a receiver and I heard nothing, let me know when you make a contact or maybe I should dig a little bit deeper! Art Art the basic problem is art that you forget we had a long conversation about what a 'gaussian' antenna in your dream was. and you specifically said a single halfwave dipole was a 'gaussian' antenna. you can go back and search if you like, but i doubt that you will since you have now changed your imaginary antenna. please art, go take a long walk... a very long walk, the fresh air may do you good. |
New antenna
On 13 Oct, 06:28, "Richard Fry" wrote:
"Dave" wrote and ONE MORE TIME.... define 'equilibrium'. write the equations. just what is in 'equilibrium' with what?? __________ snip commercial AM broadcast stations, and its very high system radiation efficiency has been proven thousands of times since the earliest days of broadcasting. Of course that is at odds with the beliefs Art continues to post here and elsewhere. In a response to my emails Art seemed to understand, and even thanked me for "sticking with it." But I guess he was not convinced, because he started this thread _after_ our email exchange. RF When a person E mails me in private he is suggesting an element of trust ie that it is private. When you betray that trust you can forget about any future discussion, private by E mail or public via the group Art Since my discussions with Art I put together a chart showing the groundwave field generated at 1 km by several, fractional wavelength monopoles at applied powers from 1-10 kW (see link below). I used a perfect ground plane in preparing the chart, but the values would be only slightly less with a 2-ohm r-f ground. ART: Note that the 1 kW field for the 1/4-wave monopole is exactly the peak field of a 1/2-wave dipole in free space (about 313 mV/m). Taller monopoles generate more groundwave field, given the same applied power and r-f ground, because their radiation patterns have more gain in the horizontal plane and less gain in other directions -- not because they are more "efficient." All of the monopoles in this chart radiate all of the power applied to them (100% efficient). Also note, Art, that a 1/2-wave monopole and its ground image comprise a full-wave antenna (eg, having your "equilibrium"), yet the 195-degree and 225-degree monopoles produce higher groundwave fields, even though they are NOT by your definition "in equilibrium." http://i62.photobucket.com/albums/h8...veFieldvsPower... RF |
New antenna
"art" wrote
Back to the Vincent antenna, he has designed an antenna that is shorter than that known before. .... The input impedance is an advantage over similar antennas and at the same time not requiring a ground plain without being a problem to the transmitter. He is also radiating well in comparison to the height of antenna and the radiating system has the appearance of being efficient. ___________ Probably you'll agree that good, new antenna designs need more than "the appearance of being efficient." Let's expand on this.. The link below leads to a calculation of the system radiation efficiency and r-f bandwidth of a conventional, 30-degree, base-loaded monopole, using the equations found in standard antenna engineering texts. This is the physical height used for the "standard DLM" antennas tested by the Navy for the University of Rhode Island. The coil and r-f ground loss was set to 2 ohms, total, to approximate the conditions in the U-RI test. This non-DLM configuration of a short monopole has a system radiation efficiency of about 59%, and for 1 kW of applied power generates an inverse distance groundwave field of 241 mV/m at 1 km. A standard, 1/4-wave vertical monopole with a matching network and r-f ground loss of 2 ohms, total, is about 95% efficient, and for 1 kW of applied power generates an inverse distance groundwave field of about 306 mV/m at 1 km. So the field of the 30-degree radiator is about 2.07 dB below that of the 90-degree radiator -- and that is due mostly to the much lower radiation resistance of the 30-degree radiator (about 2.9 ohms vs about 36 ohms) against the 2 ohms of other losses in each system. The March 31, 2005 U-RI test report states that the 3.5 MHz standard DLM had a measured groundwave field at 1 mile that was 2.33 dB less than the Navy's reference monopole (whose electrical height is not stated, but presumably is 90 degrees). So the measured h-plane gain of that DLM was about 0.26 dB _less_ than a conventional, base-loaded, 30-degree monopole -- although that difference could be within the range of measurement and/or modeling error. Also note, Art, that the DLM needs a good r-f ground, just as do all monopoles, and especially short ones. The Navy went to great effort to provide a very good r-f ground and propagation path for the range where the DLM was tested. http://i62.photobucket.com/albums/h8...rtMonopole.gif RF |
New antenna
On Oct 13, 9:06 pm, "Jimmie D" wrote:
"Richard Fry" wrote in message http://home.comcast.net/~disk100/waiting.htm |
New antenna
On Oct 13, 9:28 pm, "Richard Fry" wrote:
I must agree with Art, I think you have displayed a complete lack of good manners, what is written in private should stay as such unless agreed otherwise by both parties. Derek |
New antenna
On 14 Oct, 02:07, Derek wrote:
On Oct 13, 9:28 pm, "Richard Fry" wrote: I must agree with Art, I think you have displayed a complete lack of good manners, what is written in private should stay as such unless agreed otherwise by both parties. Derek Gentlemen I tuned my antenna this afternoon for 1.9 Mhz where the S meter was regesting S9 noise. Put a sheet of aluminium under it and the noise stayed at S9 Now I need to put a sheet of aluminium on the top of it to form a capacitor but that I can't do by myself as I need another pair of hands to rest it on the top. Hopefully my niehbor will show his face sometime in the next couple of weeks so I can complete the experiment. I made the antenna as large as I could so when it is inbetween the two 8 X 4 sheets I will see a difference in signal. Time to mow the grass for the last time and empty the gas tank for the winter. Art KB9MZ |
New antenna
On Sun, 14 Oct 2007 14:33:06 -0700, art wrote:
I tuned my antenna this afternoon for 1.9 Mhz where the S meter was regesting S9 noise. Does this antenna get a gain of 3dB more noise? 73's Richard Clark, KB7QHC |
New antenna
art wrote:
... Time to mow the grass for the last time and empty the gas tank for the winter. Art KB9MZ Be lazy--just dump a bit of gas stabilizer in! ;-) JS |
New antenna
On 14 Oct, 16:55, "Jimmie D" wrote:
"John Smith" wrote in message ... art wrote: ... Time to mow the grass for the last time and empty the gas tank for the winter. Art KB9MZ Be lazy--just dump a bit of gas stabilizer in! ;-) JS And crank it once a month Jimmie Finally got the aluminium sheets secured and now I have to find a microphone so I can work some low power over the next two weeks. I am anxious to see if it will duplicale the bottom antenna of a stack where the capacitor/antenna bleeds off noise to the ground. Antenna will stay sitting on the ground until I get a feel of how it reacts in the coming days of showers. It is set up as a cloud burner at the moment so I should get some contacts. All bands seem to be active so I will put a chair in the yard and play Maybe even take a photo for the record! Plenty of harmonics so most bands should be available Art Art |
New antenna
On Oct 9, 11:35 pm, John Smith wrote:
art wrote: www.newswise.com/articles/view/532935 Yeah, ole' Robert Vincent is a sore spot in the NG, I'd imagine. Made A$$'es out of all the "experts" and continues to do so ... sometimes there is real justice. Regards, JS I especially liked the experts who wouldn't use a B&W antenna under any circumstance because it was inefficient. Even when the uses included ALE, frequent frequency changes, and use in hostile environments. They just gotta squeeze every last db out of a piece of wire. |
New antenna
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New antenna
On 17 Oct, 21:56, Roy Lewallen wrote:
wrote: I especially liked the experts who wouldn't use a B&W antenna under any circumstance because it was inefficient. Even when the uses included ALE, frequent frequency changes, and use in hostile environments. They just gotta squeeze every last db out of a piece of wire. Any "expert" who doesn't consider the application is no expert at all, and certainly not even a competent engineer. Who are these people you're speaking of, and why do you consider them "experts"? Roy Lewallen, W7EL Interesting aproach as to what a good engineer is. It goes without saying that the application has to be considered, even Yogi Bear would have come up with a better one than that and he is not an engineer. As an engineer myself I consider a engineer or "expert" is one that will consider anything unless science has definitely ruled it out and that doesn't neccesarily include what has been written before the question arises. Natuarally that means not ruling out trying ANYTHING unless one considers their minds developed enough that it is satisfactory to go thru the thought processes only. On that basis this newsgroup is full of fake " experts"! Art KB9MZ |
New antenna
Roy Lewallen wrote:
... speaking of, and why do you consider them "experts"? Roy Lewallen, W7EL YEAH! And besides, "Where's the beef?" ;-) JS |
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