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#1
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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 |
#2
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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 |
#3
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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. |
#4
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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?? __________ 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 |
#5
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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 |
#6
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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 |
#7
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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 |
#8
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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 |
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