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Since we are at the low sun cycle I shoose
1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG |
Reflector mesh surface
Art Unwin wrote:
Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. -- Jim Pennino Remove .spam.sux to reply. |
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On Nov 30, 5:55*pm, wrote:
Richard Clark wrote: On Sun, 30 Nov 2008 21:45:03 GMT, wrote: Art Unwin wrote: Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. Hi Jim, You neglect to mention that a 3 meter dish would be wholly (no pun intended) transparent to RF in the top band. *It could be solid metal to no notice by a radiator (or receiver). It would be like blocking the sound 3 feet from the stage at a Led Zepplin concert with a Japanese parasol. * -Huh?- 73's Richard Clark, KB7QHC Yeah, I foolishly forgot the source of the question and assumed "top band" meant highest useable frequency. Unless I hosed the math, a 3 m dish would be a little over 10 db isotropic at 2 m, so the combinatation would "work" from 2 m to 23 cm. -- Jim Pennino Remove .spam.sux to reply. I ask the question because the radiator is a helix end fed, helix being approx 0.3 M diameter. Intuitively, I thought that the 3 M dish would be large enough and thus needed a check on the perforations. Could you show how the "combination" changed things so drastically so I may benefit from the question? I stated "intuitively" since the radiation is axia with respect to the helix Many thanks Art |
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On Sun, 30 Nov 2008 23:55:02 GMT, wrote:
Richard Clark wrote: On Sun, 30 Nov 2008 21:45:03 GMT, wrote: Art Unwin wrote: Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. Hi Jim, You neglect to mention that a 3 meter dish would be wholly (no pun intended) transparent to RF in the top band. It could be solid metal to no notice by a radiator (or receiver). It would be like blocking the sound 3 feet from the stage at a Led Zepplin concert with a Japanese parasol. -Huh?- 73's Richard Clark, KB7QHC Yeah, I foolishly forgot the source of the question and assumed "top band" meant highest useable frequency. Unless I hosed the math, a 3 m dish would be a little over 10 db isotropic at 2 m, so the combinatation would "work" from 2 m to 23 cm. Well, if you take the question literally, the aperature of a 3 meter dish is ummm.... 3 meters. If he had said effective aperature, the answer might be different. As for top band (160 meters), he might be referring to a chicken wire ground. This looks marginally applicable: http://lists.contesting.com/_topband/2002-09/msg00005.html Maybe he's thinking of burying his 3 meter dish and using it as a ground radial system? Incidentally, I've had rather bad luck using twisted galvanized chicken wire for making dish antennas. I kept getting intermittent noise crashes and arcing like noise bursts on a 1.7GHz WX satellite system I once threw together. I eventually found that banging on the chicken wire would produce the same noise bursts. I didn't bother trying to find out exactly what was doing the arcing. When I switched to using aluminum flashing and aluminum duct tape for the reflector, the noise went away. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
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Jeff Liebermann wrote:
Incidentally, I've had rather bad luck using twisted galvanized chicken wire for making dish antennas. I kept getting intermittent noise crashes and arcing like noise bursts on a 1.7GHz WX satellite system I once threw together. I eventually found that banging on the chicken wire would produce the same noise bursts. I didn't bother trying to find out exactly what was doing the arcing. When I switched to using aluminum flashing and aluminum duct tape for the reflector, the noise went away. I've read some reports that such is due to the poor contact of the twists in chicken wire. I suppose soldering all the twists would fix it. -- Jim Pennino Remove .spam.sux to reply. |
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Art Unwin wrote:
On Nov 30, 5:55Â*pm, wrote: Richard Clark wrote: On Sun, 30 Nov 2008 21:45:03 GMT, wrote: Art Unwin wrote: Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. Hi Jim, You neglect to mention that a 3 meter dish would be wholly (no pun intended) transparent to RF in the top band. Â*It could be solid metal to no notice by a radiator (or receiver). It would be like blocking the sound 3 feet from the stage at a Led Zepplin concert with a Japanese parasol. Â* -Huh?- 73's Richard Clark, KB7QHC Yeah, I foolishly forgot the source of the question and assumed "top band" meant highest useable frequency. Unless I hosed the math, a 3 m dish would be a little over 10 db isotropic at 2 m, so the combinatation would "work" from 2 m to 23 cm. -- Jim Pennino Remove .spam.sux to reply. I ask the question because the radiator is a helix end fed, helix being approx 0.3 M diameter. Intuitively, I thought that the 3 M dish would be large enough and thus needed a check on the perforations. Could you show how the "combination" changed things so drastically so I may benefit from the question? I stated "intuitively" since the radiation is axia with respect to the helix Many thanks Art A helix doesn't radiate in the axial mode unless the circumference is between about 0.75 and 1.33 wavelengths. The would put the minimum frequency for a .3 m diameter helix at about 240 Mhz and the maximum frequency at about 420 Mhz. Also, the reflector for a helix is a flat surface, not a dish, and is normally between about 0.8 to 1.1 wavelengths in diameter. If you make it larger, the sidelobe levels increase. -- Jim Pennino Remove .spam.sux to reply. |
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On Nov 30, 7:05*pm, wrote:
Art Unwin wrote: On Nov 30, 5:55*pm, wrote: Richard Clark wrote: On Sun, 30 Nov 2008 21:45:03 GMT, wrote: Art Unwin wrote: Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. Hi Jim, You neglect to mention that a 3 meter dish would be wholly (no pun intended) transparent to RF in the top band. *It could be solid metal to no notice by a radiator (or receiver). It would be like blocking the sound 3 feet from the stage at a Led Zepplin concert with a Japanese parasol. * -Huh?- 73's Richard Clark, KB7QHC Yeah, I foolishly forgot the source of the question and assumed "top band" meant highest useable frequency. Unless I hosed the math, a 3 m dish would be a little over 10 db isotropic at 2 m, so the combinatation would "work" from 2 m to 23 cm. -- Jim Pennino Remove .spam.sux to reply. I ask the question because the radiator is a helix end fed, helix being approx 0.3 M diameter. Intuitively, I thought that the 3 M dish would be large enough and thus needed a check on the perforations. Could you show how the "combination" changed things so drastically so I may benefit from the question? I stated "intuitively" since the radiation is axia with respect to the helix Many thanks Art A helix doesn't radiate in the axial mode unless the circumference is between about 0.75 and 1.33 wavelengths. The would put the minimum frequency for a .3 m diameter helix at about 240 Mhz and the maximum frequency at about 420 Mhz. Also, the reflector for a helix is a flat surface, not a dish, and is normally between about 0.8 to 1.1 wavelengths in diameter. If you make it larger, the sidelobe levels increase. -- Jim Pennino Remove .spam.sux to reply. No, No, No. That is not correct. Just as Kraus over estimated the gain of helix antennas he also made a mistake in specifying a particular helix angle as well as the impression that one needs a large diameter helix with reference to wave length. Ofcourse his work is over 50 years old and is being wittled down with futher investigation. I modeled it against perfect ground as the latest papers state that a wall around the bottom where there is maximum current provides best gain. Thus I see the deep and large diameter dish as being an equivalent. If .1 WL is a rule of thumb then it would seem your first response is correct. That is my personal view but I am open to contradiction hopefully with reasons why Art |
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Art Unwin wrote:
On Nov 30, 7:05Â*pm, wrote: Art Unwin wrote: On Nov 30, 5:55Â*pm, wrote: Richard Clark wrote: On Sun, 30 Nov 2008 21:45:03 GMT, wrote: Art Unwin wrote: Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. Hi Jim, You neglect to mention that a 3 meter dish would be wholly (no pun intended) transparent to RF in the top band. Â*It could be solid metal to no notice by a radiator (or receiver). It would be like blocking the sound 3 feet from the stage at a Led Zepplin concert with a Japanese parasol. Â* -Huh?- 73's Richard Clark, KB7QHC Yeah, I foolishly forgot the source of the question and assumed "top band" meant highest useable frequency. Unless I hosed the math, a 3 m dish would be a little over 10 db isotropic at 2 m, so the combinatation would "work" from 2 m to 23 cm. -- Jim Pennino Remove .spam.sux to reply. I ask the question because the radiator is a helix end fed, helix being approx 0.3 M diameter. Intuitively, I thought that the 3 M dish would be large enough and thus needed a check on the perforations. Could you show how the "combination" changed things so drastically so I may benefit from the question? I stated "intuitively" since the radiation is axia with respect to the helix Many thanks Art A helix doesn't radiate in the axial mode unless the circumference is between about 0.75 and 1.33 wavelengths. The would put the minimum frequency for a .3 m diameter helix at about 240 Mhz and the maximum frequency at about 420 Mhz. Also, the reflector for a helix is a flat surface, not a dish, and is normally between about 0.8 to 1.1 wavelengths in diameter. If you make it larger, the sidelobe levels increase. -- Jim Pennino Remove .spam.sux to reply. No, No, No. That is not correct. Yes, yes, yes, it is all corrct. Just as Kraus over estimated the gain of helix antennas he also made a mistake Nothing was said about gain. in specifying a particular helix angle Nothing was said about the helix angle. as well as the impression that one needs a large diameter helix with reference to wave length. A circumferance of 0.75 to 1.33 wavelengths is required for radiation in the axial mode. Ofcourse his work is over 50 years old and is being wittled down with futher investigation. Nope; correctness has no expiration date. I modeled it against perfect ground A pointless exercise. as the latest papers state that a wall around the bottom where there is maximum current provides best gain. What papers are these; the ones from the outhouse? A short "wall" around the outer edge of the reflector reduces side lobes. Thus I see the deep and large diameter dish as being an equivalent. Most people would call that delusional. If .1 WL is a rule of thumb then it would seem your first response is correct. Of course my first response was correct; things smaller than 0.1 wavelengths can usually be ignored. -- Jim Pennino Remove .spam.sux to reply. |
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On Nov 30, 7:55*pm, wrote:
Art Unwin wrote: On Nov 30, 7:05*pm, wrote: Art Unwin wrote: On Nov 30, 5:55*pm, wrote: Richard Clark wrote: On Sun, 30 Nov 2008 21:45:03 GMT, wrote: Art Unwin wrote: Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG The rule of thumb is things less that .1 wavelengths in size have negligable effects, so roughly up to about 1 GHz. Hi Jim, You neglect to mention that a 3 meter dish would be wholly (no pun intended) transparent to RF in the top band. *It could be solid metal to no notice by a radiator (or receiver). It would be like blocking the sound 3 feet from the stage at a Led Zepplin concert with a Japanese parasol. * -Huh?- 73's Richard Clark, KB7QHC Yeah, I foolishly forgot the source of the question and assumed "top band" meant highest useable frequency. Unless I hosed the math, a 3 m dish would be a little over 10 db isotropic at 2 m, so the combinatation would "work" from 2 m to 23 cm. -- Jim Pennino Remove .spam.sux to reply. I ask the question because the radiator is a helix end fed, helix being approx 0.3 M diameter. Intuitively, I thought that the 3 M dish would be large enough and thus needed a check on the perforations. Could you show how the "combination" changed things so drastically so I may benefit from the question? I stated "intuitively" since the radiation is axia with respect to the helix Many thanks Art A helix doesn't radiate in the axial mode unless the circumference is between about 0.75 and 1.33 wavelengths. The would put the minimum frequency for a .3 m diameter helix at about 240 Mhz and the maximum frequency at about 420 Mhz. Also, the reflector for a helix is a flat surface, not a dish, and is normally between about 0.8 to 1.1 wavelengths in diameter. If you make it larger, the sidelobe levels increase. -- Jim Pennino Remove .spam.sux to reply. No, No, No. That is not correct. Yes, yes, yes, it is all corrct. Just as Kraus over estimated the gain of helix antennas he also made a mistake Nothing was said about gain. in specifying a particular helix angle Nothing was said about the helix angle. as well as the impression that one needs a large diameter helix with reference to wave length. A circumferance of 0.75 to 1.33 wavelengths is required for radiation in the axial mode. Ofcourse his work is over 50 years old and is being wittled down with futher investigation. Nope; correctness has no expiration date. I modeled it against perfect ground A pointless exercise. as the latest papers state that a wall around the bottom where there is maximum current provides best gain. What papers are these; the ones from the outhouse? A short "wall" around the outer edge of the reflector reduces side lobes. Thus I see the deep and large diameter dish as being an equivalent. Most people would call that delusional. I am aware of that. One person once said the world was round! If one was persuasive enough at the beginninghundred years or so later if one said the world was flat he would be called delusional. If one was very persuasive in the first place he would be rediculed as it was so obvious to all in the first place. I hope you get to live another hundred years so that you can meld into the new crowd of lemmings Regards Art If .1 WL is a rule of thumb then it would seem your first response is correct. Of course my first response was correct; things smaller than 0.1 wavelengths can usually be ignored. -- Jim Pennino Remove .spam.sux to reply. |
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Art wrote:
"I stated "intuitively" since the radiation is axia with respect to the helix." A 3 M diameter has about 9.42 M circumference so becomes an effective axial radiator instead of a radial radiator at the frequency near where its circumference becomes one wavelength. This frequency is 300/(pi)(diameter) or about 10 MHz. A reflecting surface to make an axial helix unidirectional needs to be at least as large as the projection of the helix on the surface of the reflector. Its diameter should then be about 3 M or more and would be effective only at frequencies exceeding 10 MHz which is where the helix becomes an end-fire device anyway. Best regards, Richard Harrison, KB5WZI |
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I wrote:
"A 3 M diameter has about 9.42 M circumference so becomes effective as its circumference is about one wavelength or about 11.8 MHz. At lower frequencies radiation from a helix is radial rather than axial." Rounding: 300/10M=30 Mhz. Likewise: 300/1M=300 Mhz. If Art`s helix is only about 1 meter in circumference, not 10 meters, it will only be effective as an end-fire antenna above about 300 MHz, not 30 MHz. The good news is that his reflector can be proportionally smaller. Best regards, Richard Harrison, KB5WZI |
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On Dec 1, 1:42*am, (Richard Harrison) wrote:
Art wrote: "I stated "intuitively" since the radiation is axia with respect to the helix." A 3 M diameter has about 9.42 M circumference so becomes an effective axial radiator instead of a radial radiator at the frequency near where its circumference becomes one wavelength. This frequency is 300/(pi)(diameter) or about 10 MHz. A reflecting surface to make an axial helix unidirectional needs to be at least as large as the projection of the helix on the surface of the reflector. Its diameter should then be about 3 M or more and would be effective only at frequencies exceeding 10 MHz which is where the helix becomes an end-fire device anyway. Best regards, Richard Harrison, KB5WZI Richard That is good information that has a trend to my way of thinking. A heads up as to where this information comes from would be very helpfull to me in my on going experiments These ratios of diameter to length does have a penalty in wavelengths used but hopefully in less reflector diameter which is not to be viewed as a phase enabling point of view If one viewed a helix as an array of loop radiators then phasing would be important but then prevents the formation of smaller volume radiation designs. For those who rely solely on "off the cuff" thoughts may well deride what I am doing but I have done my homework and am now pursueing implematation since experiments consist of more than the exercises of the brain without the need of personal observations, without which advances would be crippled and science laboratories would become extinct My thinking now leans toward solenoid style with a air bound core for maximum flux density within the core in "rifle shot" pattern. I have had a similar antenna for the 80 metre band where the helix diameter is just 4" which is quite directional even tho as low as 30 feet!. Thus I am very much encouraged in this new design which is light enough for me to carry and install together with improvements added over my past effort tho it will not have the tilting feature at least not in the near future. I am anxious to add the tilting feature some time next year in an effort to extend individual QSO time as propagation changes ,but it is low on program requirements Best regards Art Unwin KB9MZ..........xg |
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On Dec 1, 10:25*am, (Richard Harrison)
wrote: I wrote: "A 3 M diameter has about 9.42 M circumference so becomes effective as its circumference is about one wavelength or about 11.8 MHz. At lower frequencies radiation from a helix is radial rather than axial." Rounding: 300/10M=30 Mhz. Likewise: 300/1M=300 Mhz. If Art`s helix is only about 1 meter in circumference, not 10 meters, it will only be effective as an end-fire antenna above about 300 MHz, not 30 MHz. The good news is that his reflector can be proportionally smaller. Best regards, Richard Harrison, KB5WZI Richard I would disagree with the above as it has it's roots in a loop array yagi style where phasing is of the essence. What Kraus did do is to destroy the notion that a radiator has to be straight to be effective which is borne out by Gauss. At the time he did his work ( over 50 years ago ) radar and other advances pointed to the use of higher frequencies and away from HF which then opened the advantages of circular polarization Thus his work to my knoweledge has not been extended to HF via known observables, an avenue ideally identified with hams with the experimental bent coupled with a technical educatioin. If others have already experimented in this particular area I would be happy to hear of their experiences and actual scalar obsevables. The fact that my full scale experiments have exposed facts that are contrary to that of 50 years ago is what drives me on this task tho the labour tasking can sometimes be exaspirating but non the less necessary rather than relying solely on just personal thoughts, intuitions and deductions,After all I am a qualified engineer and certainly would not have got very far in life if I thought a testing regimen is not a requirement any more Regards Art Unwin.......xg |
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On Mon, 1 Dec 2008 08:27:22 -0800 (PST), Art Unwin
wrote: I have had a similar antenna for the 80 metre band where the helix diameter is just 4" which is quite directional even tho as low as 30 feet!. My transistor radio antenna of 50 years ago was smaller than that and could do better at lower frequencies: Triple the wavelength, 4 times smaller, and at one tenth the height. That is a 120 fold advantage over your design. It cost $12, and the antenna came with it for free! 73's Richard Clark, KB7QHC |
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"Art Unwin" wrote in message ... Since we are at the low sun cycle I shoose 1" hexigon poultry wire for the mash on my 3 metre dish At what frequency will there be a noticable effect on aperture starting with top band? Many thanks Art KB9MZ...,XG he's sucking you all in now... 'TOP BAND'!!! yes, he means a 3m DISH as a reflector for his axial mode helix that is probably only inches in diameter on 160m! this is his dream 'rifle shot' antenna! |
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Art wrote:
"I would disagree with the above as it has its roots in a large yagi style where phasing is of the essence." Kraus says on page 268 of the 3rd edition of "Antennas": "The natural adjustment of phase velocity so that the fields from each turn add nearly in phase in the axial direction accounts for the persistence of the axial mode of radiation over a nearly 2 to 1 range in frequency." In Kraus` 1950 version of "Antennas" on page 178 he writes: "A first-order transmission mode on the helix, designated T1, becomes permissible when the helix circumference lambda in free space is of the order of 1 wavelength." I don`t argue with Terman or Kraus. Best regards, Richard Harrison, KB5WZI |
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On Dec 1, 11:38*pm, (Richard Harrison)
wrote: Art wrote: "I would disagree with the above as it has its roots in a large yagi style where phasing is of the essence." Kraus says on page 268 of the 3rd edition of "Antennas": "The natural adjustment of phase velocity so that the fields from each turn add nearly in phase in the axial direction accounts for the persistence of the axial mode of radiation over a nearly 2 to 1 range in frequency." In Kraus` 1950 version of "Antennas" on page 178 he writes: "A first-order transmission mode on the helix, designated T1, becomes permissible when the helix circumference lambda in free space is of the order of 1 wavelength." I don`t argue with Terman or Kraus. Best regards, Richard Harrison, KB5WZI I see no problem with it either, what is the point of the above? They both have said a lot of things that I agree with. Really Richard you needed to start another thread if you had a particular point in mind |
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JosephKK wrote:
wrote: I've read some reports that such is due to the poor contact of the twists in chicken wire. I suppose soldering all the twists would fix it. Probably would, but sounds damn tiresome. Hardware cloth is already soldered. -- 73, Cecil http://www.w5dxp.com |
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On Dec 2, 6:09*am, Cecil Moore wrote:
JosephKK wrote: wrote: I've read some reports that such is due to the poor contact of the twists in chicken wire. I suppose soldering all the twists would fix it. Probably would, but sounds damn tiresome. Hardware cloth is already soldered. -- 73, Cecil *http://www.w5dxp.com Problem there Cecil is the windmill effect on the rotor. Even tv antennas in the Midwest get a hammering while power generastor windmills are sprouting all over the place to harvest same. One of these huge windmills lost one of its blades a short time ago |
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Art Unwin wrote:
... Problem there Cecil is the windmill effect on the rotor. Even tv antennas in the Midwest get a hammering while power generastor windmills are sprouting all over the place to harvest same. One of these huge windmills lost one of its blades a short time ago Hardware cloth, cheap, indestructible, easy, widely-available, etc. ... don't under rate it! Regards, JS |
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John Smith wrote:
Hardware cloth, cheap, indestructible, easy, widely-available, etc. ... don't under rate it! Also makes a good top hat. -- 73, Cecil http://www.w5dxp.com |
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In article ,
Cecil Moore wrote: John Smith wrote: Hardware cloth, cheap, indestructible, easy, widely-available, etc. ... don't under rate it! Also makes a good top hat. but not as good as Good Old Tinfoil, for stopping Alien Mind Probes..... |
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On Dec 3, 6:14*am, Cecil Moore wrote:
John Smith wrote: Hardware cloth, cheap, indestructible, easy, widely-available, etc. ... don't under rate it! Also makes a good top hat. -- 73, Cecil *http://www.w5dxp.com Cecil The antenna will be capable of use on ALL frequency so I will be able to observe the ups and downs of the reflectors applicability when I get it up. 7 inches of snow with two more clippers on the way has put a crimp in my immediate plans My thinking is that as the antenna is end fed the need for extra large size reflecter goes out the windown as the reflector may perform as a flux guide similar to a long solenoid. This is new ground so I do not want to nickel and dime it to death until I have more experience under my belt. Present dish education is heavily weighted to phase methods used in planar designs or alternatively solely on VHF, the later being slanted designs via pitch and other factors that do not apply in my case. since my design evolves around equilibrium . I would also point out that some of Kraus's work is being thrashed with respect to gain and may well extend to use of deductions instead of observables which was heavily used in empirical gains with respect to pitch angles. Bottom line at the moment is that the antenna for top band be light and small enough for me to handle on the towerand on the ground without the need for me use my prop pitch rotor, which by itself is a handfull or to call for additional help. If I can't handle it alone then it defeats my original object with respect to small antennas without the normal compromises with respect to electrical wavelength. That ofcourse does not rule out diode action in the short run with respect to poultry fence mesh as a reflector. Regards Art |
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Art Unwin wrote:
7 inches of snow with two more clippers on the way has put a crimp in my immediate plans Hmmmmm, I don't seem to have that problem here in East Texas. Y'all come on down. -- 73, Cecil http://www.w5dxp.com |
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Cecil Moore wrote:
Art Unwin wrote: 7 inches of snow with two more clippers on the way has put a crimp in my immediate plans Hmmmmm, I don't seem to have that problem here in East Texas. Y'all come on down. We have heard rumors of that stuff here in California ... ;-) Regards, JS |
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Art Unwin wrote:
Cecil The antenna will be capable of use on ALL frequency so I will be able to observe the ups and downs of the reflectors applicability when I get it up. ... Regards Art It would seem to me, there are but two ways to couple to the ether, either capacitively or inductively, if such is even possible (there could be "something else", who knows?) At a certain ratio of capacitance to inductance, in the design of an antenna, that "magical/mystical value" of 477 ohms would be reached. However, you emphasize the inductive coupling ... I see other antennas emphasizing e and h fields and all sorts of stuff in between. In all this mumbo-jumbo something may, indeed, exist ... to date, "I just don't get it" ... Regards, JS |
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On Dec 3, 10:09*pm, John Smith wrote:
Art Unwin wrote: Cecil The antenna will be capable of use on ALL frequency so I will be able *to observe the ups and downs of the reflectors applicability when I get it up. ... Regards Art It would seem to me, there are but two ways to couple to the ether, either capacitively or inductively, if such is even possible (there could be "something else", who knows?) At a certain ratio of capacitance to inductance, in the design of an antenna, that "magical/mystical value" of 477 ohms would be reached. However, you emphasize the inductive coupling ... I see other antennas emphasizing e and h fields and all sorts of stuff in between. I don't emphasize inductive coupling, at least not with what I am messing with now! Inductive coupling infers planar antennas acting solely on intercoupling of elements while at the same time ignoring the edict of equilibrium that goes with all laws of science such that the effects of the "weak force" are ignored. With inter coupling of elements you only get approximations as the last element of any array reradiates half of that which it receives. Thus the array always needs another element regardles of the number used to obtain maximum radiation. In the case of array in equilibrium you always reach finality with respect to radiation. All very simple. On the other hand this 477 ohms figure certainly is mystical to me, what is the point you are trying to make? Is it possible that the figure you are using is bigger than you intended by being larger than life itself In all this mumbo-jumbo something may, indeed, exist ... to date, "I just don't get it" . I will take a wild guess here and assume there is some connection to the aether which is eternally on your mind. Well John for equilibrium the aether is contained within an arbitrary border. That means that all forces add up to zero, a simple concept of Newton which also means that the contents are not nothing or a vacuum what ever that is in celestial terms otherwise the border collapses. You must also realize that what is within the border must be in a state of spin as well as being in equilibrium where spin requires the present of matter. So now you have a basis on which one can define the Aether which is something other than nothing or a vacuum. Knowing that particles flow thu this that is surrounded by an arbitrary border one could possibly state that for every addition of a transient particle another particle must leave and since particles atract or repel that which is in circulation in spin form must in fact be cluster form of particles. So John let your mind have a smidgeon of freedom accepting what is known and put things together the best way you can so that you have a datum line to build on or change as knoweledge increases which allows the addition of logic by the removal of past theoretical assemblies. All the above is material that you can use in your determination if I am of sane mind or not. But first you must set your mind free accepting only that which you can personally derive from first principles as something that can be built upon. Brrrrr it is geting cold Goodnight Art ... Regards, JS |
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In article , John Smith
wrote: Cecil Moore wrote: Art Unwin wrote: 7 inches of snow with two more clippers on the way has put a crimp in my immediate plans Hmmmmm, I don't seem to have that problem here in East Texas. Y'all come on down. We have heard rumors of that stuff here in California ... ;-) Regards, JS Yeah, and in Texas you get other stuff on your boots instead of snow ;-)) Sincerely, (hey I voted for that Texan who got to be POTUS), John Wood (Code 5550) e-mail: Naval Research Laboratory 4555 Overlook Avenue, SW Washington, DC 20375-5337 |
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John Smith wrote:
At a certain ratio of capacitance to inductance, in the design of an antenna, that "magical/mystical value" of 477 ohms would be reached. Rumors are that California is in a different universe. Guess that "477 ohms" proves it. :-) -- 73, Cecil http://www.w5dxp.com |
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J. B. Wood wrote:
Yeah, and in Texas you get other stuff on your boots instead of snow ;-)) Have you seen the "Ski Texas" poster? A guy skiing down a pile of cow paddies. :-) -- 73, Cecil http://www.w5dxp.com |
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Art Unwin wrote:
... On the other hand this 477 ohms figure certainly is mystical to me, what is the point you are trying to make? Is it possible that the figure you are using is bigger than you intended by being larger than life itself Oh, I WOULD propose that 477 ohms is "real"; indeed, it as real as gravity. That is the ONLY reason you would find it in antenna calculations and mentioned in books ... however, you are quite correct, it seems it only serves as a "placeholder" and as a "magical number"--its' only purpose, to make equations and assumptions work which would otherwise not ... what that 477 ohms "really is", is the crux of an important omission/guess/fudge-factor/etc. ... All the above is material that you can use in your determination if I am of sane mind or not. But first you must set your mind free accepting only that which you can personally derive from first principles as something that can be built upon. Brrrrr it is geting cold Goodnight Art Art, I believe you sane enough, you simply "poke at matters" which are taboo ... and, I am loathe to be more specific. You either see the discontinuities which prevent "the picture from being complete", or you do not. If I felt I could go even further out on a limb, I would. For now there are only questions and a search through others thoughts ... Regards, JS |
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Cecil Moore wrote:
... Rumors are that California is in a different universe. Guess that "477 ohms" proves it. :-) Your point being well taken, I can only reply, "477 ohms can ONLY be as important as the equations which depend upon it to function." Regards, JS |
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Cecil Moore wrote:
John Smith wrote: At a certain ratio of capacitance to inductance, in the design of an antenna, that "magical/mystical value" of 477 ohms would be reached. Rumors are that California is in a different universe. Guess that "477 ohms" proves it. :-) Oh gawd, you got me 377 (it exists in my calculator as a variable "fs" (or "free space"), I seldom enter it from a keyboard) ... its' computation given he http://whatis.techtarget.com/definit...845268,00.html I do that, yanno'? :-( Regards, JS |
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John Smith wrote:
Cecil Moore wrote: Rumors are that California is in a different universe. Guess that "477 ohms" proves it. :-) Your point being well taken, I can only reply, "477 ohms can ONLY be as important as the equations which depend upon it to function." Dang John, you missed the point. In the free space that exists in my universe in Texas that figure is 376.73031346177... ohms. Is 477 ohms the Z0 of free space in the land of fruits and nuts? :-) -- 73, Cecil http://www.w5dxp.com |
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Art Unwin wrote:
... Brrrrr it is geting cold Goodnight Art To get us closer to being on the same page: http://www.physlink.com/Education/askExperts/ae674.cfm Says it better than I ever could. Regards, JS |
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Cecil Moore wrote:
... Dang John, you missed the point. In the free space that exists in my universe in Texas that figure is 376.73031346177... ohms. Is 477 ohms the Z0 of free space in the land of fruits and nuts? :-) Cecil: LOL! I was slow on the uptake, sorry old man ... :-( I know that is a terrible sin here, one I make too frequently ... you got me! I punched [1 x "fs"] into the calculator, got the ~377 and immediately recognized my error ... just gettin' old and slow here ... It was wise of you to make a point of it ... thanks! Regards, JS |
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On Dec 4, 11:38*am, John Smith wrote:
Art Unwin wrote: * ... On the other hand this 477 ohms figure certainly is mystical to me, what is the point you *are trying to make? Is it possible that the figure you are using is bigger than you intended *by being larger than life itself Oh, I WOULD propose that 477 ohms is "real"; *indeed, it as real as gravity. *That is the ONLY reason you would find it in antenna calculations and mentioned in books ... however, you are quite correct, it seems it only serves as a "placeholder" and as a "magical number"--its' only purpose, to make equations and assumptions work which would otherwise not ... what that 477 ohms "really is", is the crux of an important omission/guess/fudge-factor/etc. ... *All the above is material that you can use in your determination if I am of sane mind or not. But first you must set your mind free accepting only that which you can personally derive from first principles as something that can be built upon. Brrrrr it is geting cold Goodnight Art Art, I believe you sane enough, you simply "poke at matters" which are taboo ... and, I am loathe to be more specific. *You either see the discontinuities which prevent "the picture from being complete", or you do not. *If I felt I could go even further out on a limb, I would. *For now there are only questions and a search through others thoughts ... Regards, JS John, my first point was the 477 error but you didn't catch on.No problem Regarding taboo. When the gloves are taken off then every thing goes !. The first person to fire does not make the rules for what then ensues. When a animal kicks you in the crotch then there is a good chance it has rabies and you do what you have to do,. Ofcourse you can run away but then that would be very painful and lasts a life time. Let it drop My very best regards Art Unwin KB9MZ.......xg |
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