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#11
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The ultimate tilted monopole
On Sep 8, 1:02*pm, Richard Fry wrote:
On Sep 8, 12:30*pm, Art Unwin wrote: So far you have shown progress by tipping the radiator where it started to fill the void at the center of the donut. This alone confirms the idea that another vector has to be considered outside the arbitrary border The change in the elevation pattern shape and gains seen in the "tipped" NEC plot I posted are NOT due to equilibrium, vectors outside boundaries, shear forces, torque, spin etc. The change in the pattern of the tipped vertical dipole are due to changes in the amount and direction of the energy radiated toward the earth by, and near the antenna, and the net field that results by the vector addition of that reflection with the energy radiated in a given direction by the dipole itself. Suggest you use NEC to model a vertical dipole in free space, at several physical rotation angles away from plumb. *See if the gain and shape of the radiation pattern changes (they won't, if your model is valid). Also note that the Poynting vector does not take the form of a perfect sphere for any linear antenna -- only for a (non-existent) isotropic radiator. RF We have now come to the end of my input. We choose to disagree. I can go along with that just to get you and others off my back. I will go away and let all mumble about things between themselves. I need a vacation this year anyway and the kids are back in school so it is a good time and the weather is just right. This month will be momentous at the UN so a seat in the gallery sound good We will see. |
#12
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The ultimate tilted monopole
On Sep 7, 6:44*pm, "christofire" wrote:
... and if that isn't enough, how about the Racal Antennas at http://www.racalantennas.com/product...45-30mhz.aspx? I just now looked at this link, and see that it states that this radiator configuration is horizontally polarized. That polarization appears to be "implausible" for this configuration. Does any scientific documentation exist, or do any measured, real- world performance results prove that this configuration truly is horizontally polarized? RF |
#13
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The ultimate tilted monopole
On Sep 8, 6:49*pm, Richard Fry wrote:
On Sep 7, 6:44*pm, "christofire" wrote: ... and if that isn't enough, how about the Racal Antennas athttp://www..racalantennas.com/products/ground/omnidirectional/hf/difan... I just now looked at this link, and see that it states that this radiator configuration is horizontally polarized. That polarization appears to be "implausible" for this configuration. Does any scientific documentation exist, or do any measured, real- world performance results prove that this configuration truly is horizontally polarized? RF You are so dumb! Look at the center pole as being a vector in opposition to the gravity vector. Then add the two tilted vectors which represents the vectors of the Coriolis force. (Yes, you add both of the vectors for Coriollis because it is a rotational force) You are then left with a horizontal vector that balances the above vectors. Thus you have horizontal polarization. Why? Because the vectors outside the boundary are a combination of two vectors which is gravity and the Coriolis. Now somebody mentioned the question of polarization purity ! When you include the Coriolis effect you get exactly that, a pure horizontal polarization which is very useful in determining whether forces in shear conditions exist at airports as views of reflection of transmissions are confusing if you transfer a mixture in the first place. This way they have purity in radiation so that reflections are more clearer for their determinations as to what weather conditions exist and hopefully not "wind shear" where a plane instantly loses altitude. You are fortunate that you caught me before I left. |
#14
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The ultimate tilted monopole
Art Unwin wrote:
On Sep 8, 6:49 pm, Richard Fry wrote: On Sep 7, 6:44 pm, "christofire" wrote: ... and if that isn't enough, how about the Racal Antennas athttp://www.racalantennas.com/products/ground/omnidirectional/hf/difan... I just now looked at this link, and see that it states that this radiator configuration is horizontally polarized. That polarization appears to be "implausible" for this configuration. Does any scientific documentation exist, or do any measured, real- world performance results prove that this configuration truly is horizontally polarized? RF You are so dumb! Look at the center pole as being a vector in Art You expect people to treat you with respect and complain when they don't. And then you treat others like SH T. And you wonder why we don't respect you. tom K0TAR |
#15
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The ultimate tilted monopole
Art Unwin wrote:
You are so dumb! Look at the center pole as being a vector in opposition to the gravity vector. Then add the two tilted vectors which represents the vectors of the Coriolis force. (Yes, you add both of the vectors for Coriollis because it is a rotational force) You are then left with a horizontal vector that balances the above vectors. Thus you have horizontal polarization. Why? Because the vectors outside the boundary are a combination of two vectors which is gravity and the Coriolis. Now somebody mentioned the question of polarization purity ! When you include the Coriolis effect you get exactly that, a pure horizontal polarization which is very useful in determining whether forces in shear conditions exist at airports as views of reflection of transmissions are confusing if you transfer a mixture in the first place. This way they have purity in radiation so that reflections are more clearer for their determinations as to what weather conditions exist and hopefully not "wind shear" where a plane instantly loses altitude. You are fortunate that you caught me before I left. And I have to say, WHAT A LOAD OF RUBBISH!! Give me the vectors for all forces involved. The description alone is not acceptable. And none of your obfuscation BullSh t. Just do it, otherwise I know you're lying, as usual. It's not that I don't trust you, but I don't trust you. tom K0TAR |
#16
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The ultimate tilted monopole
On Sep 8, 8:19*pm, Art Unwin wrote:
On Sep 8, 6:49*pm, Richard Fry wrote: On Sep 7, 6:44*pm, "christofire" wrote: ... and if that isn't enough, how about the Racal Antennas athttp://www.racalantennas.com/products/ground/omnidirectional/hf/difan... I just now looked at this link, and see that it states that this radiator configuration is horizontally polarized. That polarization appears to be "implausible" for this configuration. Does any scientific documentation exist, or do any measured, real- world performance results prove that this configuration truly is horizontally polarized? RF You are so dumb! Look at the center pole as being a vector in opposition to the gravity vector. Then add the two tilted vectors which represents the vectors of the Coriolis force. (Yes, you add both of the vectors for Coriollis because it is a rotational force) You are then left with a horizontal vector that balances the above vectors. Thus you have horizontal polarization. Why? *Because the vectors outside the boundary are a combination of two vectors which is gravity and the Coriolis. Now somebody mentioned the question of polarization purity ! When you include the Coriolis effect you get exactly that, a pure horizontal polarization which is very useful in determining whether forces in shear conditions exist at airports as *views *of reflection of transmissions *are confusing if you transfer a mixture in the first place. This way they have purity in radiation so that reflections are more clearer for their determinations as to what weather conditions exist and hopefully not "wind shear" where a plane instantly loses altitude. You are fortunate that you caught me before I left. ROTFLAMO |
#17
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The ultimate tilted monopole
There are many spelling mistakes in your random word generator.
olivier Art Unwin wrote: On Sep 8, 11:00 am, Richard Fry wrote: In the case of a single monopole mounted with its base at earth level, adding tilt to it makes very little difference in its gain at elevation angles up to +60 degrees or so, at any azimuth. It does partially fill the elevation null at the zenith produced by the vertical monopole, as well as to produce a small amount of h-pol radiation over most of the compass. Modeling this in NEC for a 1 MHz, 1/4-wave, straight monopole by moving its top 10 meters out of plumb changed its peak gain by about 0.01 dB compared to the untilted version, at any azimuth. RF Gain has never been as issue in tipping the radiator except for some who which to interject it. Pointing's vector shows a radiation patterm that is spherical and in a state of equilibrium It is not the radiation pattern of a donut which all are familiar with. Thus if one wants coverage in all directions one must pursue an array or conductor in equilibrium. The present state of the art only considers gravity as being outside the arbitrary border such that the equal and opposite vecter is exactly that. ie at right angles to the Earth's surface. Now we all know that the radiation pattern of such does not remotely resemble that of Pointings vector! To get to the point of a spherical radiation pattern one must recognize that there is an additional vector outside the boundary that one must consider to obtain equilibrium. So far you have shown progress by tipping the radiator where it started to fill the void at the center of the donut. This alone confirms the idea that another vector has to be considered outside the arbitrary border. Now rotation is an essential property of the Universe as fracture of an arbitrary boundary is created by two forces which are not on a common plane. This is a shear force which also creates torque or spin ,so it stands to reason that the other force in combination with gravity is a force of torque or rotation. If Coriolis is not that vector what other characteristic fits the bill? |
#18
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The ultimate tilted monopole
"christofire" wrote in message ... snip Such a design also appears as a self-supporting HF receive antenna the Navy mounted on the forward gun mount. I struggled to find a picture of a ship with one showing but no luck. The elements were about five to seven feet long and arranged as the OP describes. USS Missouri http://www.kh6bb.org/photos2.html Chris Chris, that's the discone/cage, a transmit antenna with two individual feedlines from the Radio Room. Some people call it the discage, as on the website, but I never did. The cage portion radiates 4 - 12 MHz and the discone portion radiates 10-30. IIRC, it stands more than 20 feet high. The antenna I'm trying to remember was receive only and was less than 6 feet high. It had a shape that sort of resembled a squat wire basket. Sal |
#19
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The ultimate tilted monopole
"Sal M. Onella" wrote in message news "christofire" wrote in message ... snip Such a design also appears as a self-supporting HF receive antenna the Navy mounted on the forward gun mount. I struggled to find a picture of a ship with one showing but no luck. The elements were about five to seven feet long and arranged as the OP describes. USS Missouri http://www.kh6bb.org/photos2.html Chris Chris, that's the discone/cage, a transmit antenna with two individual feedlines from the Radio Room. Some people call it the discage, as on the website, but I never did. The cage portion radiates 4 - 12 MHz and the discone portion radiates 10-30. IIRC, it stands more than 20 feet high. The antenna I'm trying to remember was receive only and was less than 6 feet high. It had a shape that sort of resembled a squat wire basket. Sal Sal, There's a directory of antennas used at one time or another by the US Navy at http://www.combatindex.com/hardware/...nsor_main.html. Could it be the AS-2231? The 'discage' appears to be the AS-2802. Also, a contributor to this group, Richard Clark, has some photos at http://home.comcast.net/~kb7qhc/antennas/navy/. I was aware that the discage in at least one of its incarnations had two separate feed lines, and the combination of two antennas in one 'package' gives rise to its particular shape. However, it has always intrigued me that a single element of similar shape has been used since the early 50s by the British Navy in the AJE/UK-SRA-102: http://middle-watch.com/communications.htm and http://rnmuseumradarandcommunication...org.uk/AJE.pdf. This could be a coincidence or it could be that F. A. Kitchen, the designer of the AJE, had been influenced by having previously seen a discage (his paper about development of the AJE doesn't really explain where the shape comes from). So I wonder when the AS-2802 'discage' came into use? Chris |
#20
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The ultimate tilted monopole
"christofire" wrote in message ... snip The antenna I'm trying to remember was receive only and was less than 6 feet high. It had a shape that sort of resembled a squat wire basket. Sal Sal, There's a directory of antennas used at one time or another by the US Navy at http://www.combatindex.com/hardware/...nsor_main.html. Could it be the AS-2231? No, that's called a sleeve, I think, but I moused over the MIL nomenclatures and looked at each picture. The antenna I was thinking of is the AS-2866/SRR. I am surprised to see in the write-up that it's only 24 inches tall. I thought twice that. I used that website many times when I was working (prior to June, 2007) and was wishing I had saved the link on my home computer. Now I have it again :-))) I was aware that the discage in at least one of its incarnations had two separate feed lines, and the combination of two antennas in one 'package' gives rise to its particular shape. However, it has always intrigued me that a single element of similar shape has been used since the early 50s by the British Navy in the AJE/UK-SRA-102: http://middle-watch.com/communications.htm and http://rnmuseumradarandcommunication...org.uk/AJE.pdf. This could be a coincidence or it could be that F. A. Kitchen, the designer of the AJE, had been influenced by having previously seen a discage (his paper about development of the AJE doesn't really explain where the shape comes from). So I wonder when the AS-2802 'discage' came into use? I think it was removed from USS Dubuque (LPD-7) during the ship's overhaul in 1982/83. I was there but the memory gets a little hazy about such details. If that recollection is correct, it predates the 1980s. |
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