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Antenna optimizers
In a different thread, N5MK wrote:
I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB) http://www.ifwtech.co.uk/g3sek |
Antenna optimizers
On 9 Mar, 02:37, Ian White GM3SEK wrote:
In a different thread, N5MK wrote: I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek What bothers me about all this Ian is that AO when allowed to run freely does produces an array where all elements are resonant in situ. Put this same array in NEC4 and the program will concur with the value of the desirables given. In the early days I thought that this was a result of programming interference by outsiders but the symetry kept bugging me. So I gave a rational for why AO was correct to test the water. Well we all know that it is not in the books therefore I am an idiot. So we flip the coin and determine why the original NEC code provided an opening for such a big error but first we determine if this so called"" error" had spread in any way. Tho I believe my rational is correct surely the majority would be interested in the cause of this anomaly, why it produced antenna arrays that were legitametly smaller than the yagi and since NEC4 verified its performance it should be of interest to all antenna designers. But no. Ridicule has been put into motion and true science went out of the window. Cheers Art Go figure! |
Antenna optimizers
On Mar 9, 5:37 am, Ian White GM3SEK wrote:
In a different thread, N5MK wrote: I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek The first time I used YO was on a 386 computer and I remember how looooong it took. Not too long ago I ran it on my daugther's 3.2Ghz computer and it zipped by so fast I couldnt see what was going on. Are there new versions that take care of this timing problem? The hardest thing to do when using this type of software is to define BEST. BEST is a very subjective quality. For eample I had a vertical on 10 meters that is 1.5wl long. Most people would call this an awful antenna with a vertical radiation angle that is way too high. No doubt this wasnt the best local antenna or the best DX antenna but it filled a niche. It worked great for short range skip and allowed me to have QSOs that I never would have had with any other antenna. Seemed to really like to talk into Louisianna for some reason. Jimmie |
Antenna optimizers
On Mar 9, 9:18 am, "art" wrote:
On 9 Mar, 02:37, Ian White GM3SEK wrote: In a different thread, N5MK wrote: I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek What bothers me about all this Ian is that AO when allowed to run freely does produces an array where all elements are resonant in situ. Put this same array in NEC4 and the program will concur with the value of the desirables given. In the early days I thought that this was a result of programming interference by outsiders but the symetry kept bugging me. So I gave a rational for why AO was correct to test the water. Well we all know that it is not in the books therefore I am an idiot. So we flip the coin and determine why the original NEC code provided an opening for such a big error but first we determine if this so called"" error" had spread in any way. Tho I believe my rational is correct surely the majority would be interested in the cause of this anomaly, why it produced antenna arrays that were legitametly smaller than the yagi and since NEC4 verified its performance it should be of interest to all antenna designers. But no. Ridicule has been put into motion and true science went out of the window. Cheers Art Go figure!- Hide quoted text - - Show quoted text - Sorry but I dont understand you Art, you denounce known theory but want to use software based on known theory to prove your hypothesis. Sorry but you tend to accept or denounce current theory just so you can defend your current arguments. Jimmie |
Antenna optimizers
On 9 Mar, 09:05, "JIMMIE" wrote:
On Mar 9, 9:18 am, "art" wrote: On 9 Mar, 02:37, Ian White GM3SEK wrote: In a different thread, N5MK wrote: I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek What bothers me about all this Ian is that AO when allowed to run freely does produces an array where all elements are resonant in situ. Put this same array in NEC4 and the program will concur with the value of the desirables given. In the early days I thought that this was a result of programming interference by outsiders but the symetry kept bugging me. So I gave a rational for why AO was correct to test the water. Well we all know that it is not in the books therefore I am an idiot. So we flip the coin and determine why the original NEC code provided an opening for such a big error but first we determine if this so called"" error" had spread in any way. Tho I believe my rational is correct surely the majority would be interested in the cause of this anomaly, why it produced antenna arrays that were legitametly smaller than the yagi and since NEC4 verified its performance it should be of interest to all antenna designers. But no. Ridicule has been put into motion and true science went out of the window. Cheers Art Go figure!- Hide quoted text - - Show quoted text - Sorry but I dont understand you Art, you denounce known theory but want to use software based on known theory to prove your hypothesis. Sorry but you tend to accept or denounce current theory just so you can defend your current arguments. Jimmie- Hide quoted text - - Show quoted text - Thats an untruth Jimmie! are you only reading what you want to read? Art |
Antenna optimizers
On Mar 9, 1:58 pm, "art" wrote:
On 9 Mar, 09:05, "JIMMIE" wrote: On Mar 9, 9:18 am, "art" wrote: On 9 Mar, 02:37, Ian White GM3SEK wrote: In a different thread, N5MK wrote: I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] -- 73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)http://www.ifwtech.co.uk/g3sek What bothers me about all this Ian is that AO when allowed to run freely does produces an array where all elements are resonant in situ. Put this same array in NEC4 and the program will concur with the value of the desirables given. In the early days I thought that this was a result of programming interference by outsiders but the symetry kept bugging me. So I gave a rational for why AO was correct to test the water. Well we all know that it is not in the books therefore I am an idiot. So we flip the coin and determine why the original NEC code provided an opening for such a big error but first we determine if this so called"" error" had spread in any way. Tho I believe my rational is correct surely the majority would be interested in the cause of this anomaly, why it produced antenna arrays that were legitametly smaller than the yagi and since NEC4 verified its performance it should be of interest to all antenna designers. But no. Ridicule has been put into motion and true science went out of the window. Cheers Art Go figure!- Hide quoted text - - Show quoted text - Sorry but I dont understand you Art, you denounce known theory but want to use software based on known theory to prove your hypothesis. Sorry but you tend to accept or denounce current theory just so you can defend your current arguments. Jimmie- Hide quoted text - - Show quoted text - Thats an untruth Jimmie! are you only reading what you want to read? Art- Hide quoted text - - Show quoted text - What do you mean UNTRUE, Isnt it TRUE that you have repeatedly chastised people for only accepting that which is ACCEPTED and written in books, calling these people LEMMINGS. ISNT it also true you use the same software based on that long accepted data that you claim to be in error. Sounds to me as you want to have your cake and eat it too. Please explain how you can accept results from software that uses the theory you have denounced. Jimmie |
Antenna optimizers
Ian White GM3SEK wrote:
In a different thread, N5MK wrote: I've tried some programs with "optimizers" etc, etc.. MMANA has one fer instance, and it's freeware. In many cases, I can manually churn out a better design by ignoring it, and doing it myself. I've seen a few churn out some pretty funky designs which were not even close to being optimum. Overall, I don't have much use for them. I don't need the program to hold my hand while using it. Can we start a new discussion, specifically about optimizers? Having used Brian Beezley's YO and AO (Yagi Optimizer and Antenna Optimizer) extensively in the past, I'm not quite as pessimistic as Mark about the value of optimizers. If they're simply allowed to run wild, they can produce some very foolish antenna designs. Usually that is not a criticism of the automated modeling... it mostly means that, for some practical reason or another, the user would be a fool to build the thing. On the other hand, an optimizer can be very useful for tasks that have a very simple target, so it can't go far wrong. For example: "Adjust the length of that wire to make it resonant at this frequency." That doesn't take long to do by hand, but an optimizer can also handle more complicated tasks like: "Adjust the lengths of these three interacting wires to make the antenna resonant on three different bands." Then you really start to see some benefit from the automation. At the other end of the spectrum is the kind of complex optimization for which YO was developed. You quickly learn that you can't just say "Optimize that yagi!" Quite the opposite: to use the program at all, you are forced to think very hard about what you really mean by "optimum" - for example, how much importance you attach to forward gain, a clean pattern, a convenient feedpoint impedance, and to maintaining that good performance over a wide bandwidth. Playing with an optimizer, you quickly come to understand that it isn't possible to get the best of everything, all at the same time... which is a very valuable lesson to learn. The same applies to all other antenna optimizers, of course; and circuit optimizers too. The learning process alone can be worth the money. Having gone through that learning process, an automatic optimizer can then zip out some really good antenna designs in a matter of minutes - which leaves you wondering what took you so long :-) But that isn't going to happen in the first evening, or even maybe the first month. [Sorry, I don't know how or even if you can buy AO or YO any more.] However, there are other optimizers out there. Arie has one in 4nec2 that works fairly well. There's also a program called GENOPT which can optimize ANYTHING (or at least, anything where the modeling program can be invoked from the command line and which takes a file as input and generates a file as output).. You can specify all sorts of contstraints and evaluation functions, and it just keeps shooting new models out, running the modeler, and parsing the output. For use with NEC, you need to write a little postprocessor to extract your desired "figure of merit" from the NEC output file (e.g. NEC doesn't give you something like F/B or SWR Bandwidth.. and while the GENOPT parser *could* be set up to do it, it would be painful...) And, there's a variety of ways to do things like fire off NEC from Excel, and you can use Excel's optimizer (such as it is..). If you get into more esoteric optimizers like particle swarm or genetic optimizers, they're all available in fairly generic form. So, what you need is the following 4 pieces of softwa 1) The optimizer engine 2) Something that takes a list of "parameters being optimized" (your independent variables) and turns it into a suitable model file 3) The modeler (e.g. NEC) 4) Something that post processes the output of the modeler to generate your "evaluation function". If you can get each of the latter 3 in a form which is invokable from the command line, then almost all of the existing #1 programs can use it. For doing #2, there is a perl script/program out there that can do fairly nice parameter substitution. Not quite as nice as Arie's 4nec2 symbol substitution with math, but at least it will take a file with one parameter per line, and substitute them into a "skeleton" NEC input deck that has parameter references, with some arithmetic. There's actually a lot of these sorts of scripting tools around. for #3, it exists already for #4, it would be nice if there were a library of little programs that could parse a NEC output deck and just emit a few numbers for some standardized analyses.. For instance, you could feed in a NEC output file and it would give you front/back ratio, or SWR bandwidth. Obviously, such things exist, embedded in programs like EZNEC and 4nec2, but they're not readily available as little usable components (and I don't expect Roy or Arie to provide them, either.. That's their proprietary improvements on the raw NEC engine, and they should use them as they see fit, in exchange for the considerable work they've put into it.) Maybe a good start would be to define some common "figure of merit" numbers that might be applied to antennas. Not just define in words, but in a more rigorous quantitative specification sort of way. Some are easy (forward gain, swr bandwidth for a single band), some are more difficult.. how do you handle describing side/back lobe performance? Do you cutoff above a certain elevation angle (on the basis that there's no propagation there anyway)? The radar folks talk about things like Peak Sidelobe Level, Integrated Sidelobe Level, and average sidelobe level. Jim |
Antenna optimizers
On 9 Mar 2007 10:58:02 -0800, "art" wrote:
Sorry but I dont understand you Art, you denounce known theory but want to use software based on known theory to prove your hypothesis. Just what the Global Warming Paranoia brigade are doing these days with their climatic change modelling software!!! Peter, G3PHO |
Antenna optimizers
Peter wrote:
On 9 Mar 2007 10:58:02 -0800, "art" wrote: Sorry but I dont understand you Art, you denounce known theory but want to use software based on known theory to prove your hypothesis. Just what the Global Warming Paranoia brigade are doing these days with their climatic change modelling software!!! Peter, G3PHO Computer modeling seems to be the new shill game of street smart con men alright. However, I think antenna modeling software is in a bit different category--however, the computer model can only be as good as our understanding of "radio theory." (and note, that IS radio theory and NOT "radio laws." JS -- http://assemblywizard.tekcities.com |
Antenna optimizers
John Smith I wrote:
Peter wrote: On 9 Mar 2007 10:58:02 -0800, "art" wrote: Sorry but I dont understand you Art, you denounce known theory but want to use software based on known theory to prove your hypothesis. Just what the Global Warming Paranoia brigade are doing these days with their climatic change modelling software!!! Peter, G3PHO Computer modeling seems to be the new shill game of street smart con men alright. However, I think antenna modeling software is in a bit different category--however, the computer model can only be as good as our understanding of "radio theory." (and note, that IS radio theory and NOT "radio laws." Thus blovates another ignorant dweeb that doesn't know the word "theory" has a different meaning in science than it does in a TV mystery. -- Jim Pennino Remove .spam.sux to reply. |
Antenna optimizers
Peter wrote:
Just what the Global Warming Paranoia brigade are doing these days with their climatic change modelling software!!! Wonder what caused the Global Warming trend that began 140,000 years ago and eventually resulted in temperatures a lot higher than today? Wonder what triggered the present Global Warming trend that started 20,000 years ago? Caveman campfires? -- 73, Cecil http://www.w5dxp.com |
Antenna optimizers
wrote:
... Dweeb? Jim, are you looking in a mirror while typing your posts? Definitions of "scientific theory" on the Web: * An explanation of why and how a specific natural phenomenon occurs. A lot of hypotheses are based on theories. In turn, theories may be redefined as new hypotheses are tested. Examples of theories: Newton’s Theory of Gravitation, Darwin’s Theory of Evolution, Mendel’s theory of Inheritance, Einstein’s Theory of Relativity. www.ncsu.edu/labwrite/res/res-glossary.html * A hypothesis that is widely accepted by the scientific community. www.ametsoc.org/amsedu/WES/glossary.html * a statement that postulates ordered relationships among natural phenomena. farahsouth.cgu.edu/dictionary/ * The most logical explanation of why things work the way they do. A theory is a former hypothesis that has been tested with repeated experiments and observations and found always to work. jmsscienceweb.tripod.com/vocabulary.htm * A body of knowledge using controlled-variable experimental methods to construct a formal and mathematically structured system. It studies the character of natural reality. Scientific Management (6). System of management popular in the first decades of the 20th c. Proponants sought to transform industry, government and society through greater efficiency. Utilizes top-down approach. http://www.udmercy.edu/faculty_pages.../glossary.html * a theory that explains scientific observations; "scientific theories must be falsifiable" wordnet.princeton.edu/perl/webwn * The word theory has a number distinct meanings depending on the context. en.wikipedia.org/wiki/Scientific_theory JS -- http://assemblywizard.tekcities.com |
Antenna optimizers
"Cecil Moore" wrote in message ... Peter wrote: Just what the Global Warming Paranoia brigade are doing these days with their climatic change modelling software!!! Wonder what caused the Global Warming trend that began 140,000 years ago and eventually resulted in temperatures a lot higher than today? Wonder what triggered the present Global Warming trend that started 20,000 years ago? Caveman campfires? -- 73, Cecil http://www.w5dxp.com Algore and socialist liberal leaches looking for new "crisis" so they can justify and fool sheeple into submitting to crazy measures and spending money. Any ham knows that we are on the mercy of Ol Sun which supplies us with warmth and light and has its moods, periods and we can't do a shing about it. Hey Algore! See the temperature differences day/night, summer/winter? What causes it? CO2 or Sun's generosity? Global Scam of all times. Not even antenna optimizers or Gausian gizmos can do a thing about it. As soon as Algore got his Ossskar, God blew wave of cold to show him who is in charge :-) 73 and keep breathing out CO2 and step on the gas of your SUV, plants love it! Yuri, K3BU.us |
Antenna optimizers
Yuri Blanarovich wrote:
Any ham knows that we are on the mercy of Ol Sun which supplies us with warmth and light and has its moods, periods and we can't do a shing about it. Apparently the Martians also have too many SUVs since the Martian polar cap is shrinking. -- 73, Cecil http://www.w5dxp.com |
Antenna optimizers
"Yuri Blanarovich" wrote in
: Global Scam of all times. Not even antenna optimizers or Gausian gizmos can do a thing about it. As soon as Algore got his Ossskar, God blew wave of cold to show him who is in charge :-) So let me get this straight, Yuri, A cold snap in your neighborhood means that Global warming is invalid? I always offer this challenge: A number of gaseous components naturally occurring in the atmosphere have an effect that tends to retain heat. These are collectively referred to as greenhouse gases. That paragraph is a fact. It has been experimentally proven. Through various methods, the amount of at least one of those gases has increased significantly since the beginning of the industrial age. That is a measurable fact. note: there have been some fairly dramatic increases in other gases that are much more "actice" in heat retention, like methane. Let's ignore them for the purposes of this argument. Give me a compelling and scientific reason why proven scientific facts are not having a measurable effect on the earth's temperature. Then invalidate the apparent measured effects that would tend to support the warming. I am willing to abandon the thought of global warming if someone can give me a real and non-political argument. Of course, that means no offhand remarks about Left wingers, commies, or the usual suspect trotted out as some kind of "proof" that satisfies only those who get their science news from AM radio talkshow hosts. From a right-winger who looks beyond the politics. (p.s. no one has done it yet) - 73 de Mike KB3EIA - |
Antenna optimizers
Cecil Moore wrote in news:F1pIh.9068$jx3.404
@newssvr25.news.prodigy.net: Peter wrote: Just what the Global Warming Paranoia brigade are doing these days with their climatic change modelling software!!! Wonder what caused the Global Warming trend that began 140,000 years ago and eventually resulted in temperatures a lot higher than today? Wonder what triggered the present Global Warming trend that started 20,000 years ago? Caveman campfires? Hardly likely Cecil. The amount of CO2 in the atmosphere has varied quite a bit over time. Lot's of sources of it, and lots of sources of other greenhouse gases. Certainly the Deccan Traps indicate that volcanic activity likely had some effect on CO2 atmospheric content. That was quite a bit before 140,00 years ago. The sun itself undergoes some variability. It is likely that many things contribute to temperature variations. Human effects would hardly have made any impact before our population growth and inadvertant release of greenhouse gases did start to have that impact. Let me ask a question of the doubters. Say that a new ice age came about. Say that Canada and much of the north were starting to freeze over. In the sothern Hemisphere, the same was happening. All this was meaning that Humanity was going to loook at a huge die off, as useable land were to shrink, and the present population became unsupportable. But perhaps a way out was available. Burning as much carbon based fuels as possible would possibly raise global temperatures some. Perhaps land at the fringes would become able to support agriculture again, instead of being glaciated. Perhaps more humans could be saved. Would that be okay then? Would it be worth the effort? Or should we just die off because it was a liberal plot? ;^) - 73 de Mike KB3EIA - |
Antenna optimizers
On 9 Mar, 20:20, John Smith I wrote:
wrote: ... Dweeb? Jim, are you looking in a mirror while typing your posts? Definitions of "scientific theory" on the Web: * An explanation of why and how a specific natural phenomenon occurs. A lot of hypotheses are based on theories. In turn, theories may be redefined as new hypotheses are tested. Examples of theories: Newton's Theory of Gravitation, Darwin's Theory of Evolution, Mendel's theory of Inheritance, Einstein's Theory of Relativity. www.ncsu.edu/labwrite/res/res-glossary.html * A hypothesis that is widely accepted by the scientific community. www.ametsoc.org/amsedu/WES/glossary.html * a statement that postulates ordered relationships among natural phenomena. farahsouth.cgu.edu/dictionary/ * The most logical explanation of why things work the way they do. A theory is a former hypothesis that has been tested with repeated experiments and observations and found always to work. jmsscienceweb.tripod.com/vocabulary.htm * A body of knowledge using controlled-variable experimental methods to construct a formal and mathematically structured system. It studies the character of natural reality. Scientific Management (6). System of management popular in the first decades of the 20th c. Proponants sought to transform industry, government and society through greater efficiency. Utilizes top-down approach. http://www.udmercy.edu/faculty_pages.../glossary.html * a theory that explains scientific observations; "scientific theories must be falsifiable" wordnet.princeton.edu/perl/webwn * The word theory has a number distinct meanings depending on the context. en.wikipedia.org/wiki/Scientific_theory JS --http://assemblywizard.tekcities.com Jim, your point is excellent. Amateurs would be hard put to design an efficient radiator array using known electrical laws as stated by Maxwell. Imagine trying to design a yagi antenna using only Maxwells observations instead of the 'suck it and see' empirical methods used today. Known electrical laws are simplicity in themselves usually just a paragragh in length, could you supply the same for the Yagi? As I have stated earlier the Yagi put antenna design back by over half a century since it diverted thinking though around known electrical laws to taking the easy empirical way out. Art |
Antenna optimizers
On 25 Mar 2007 19:47:09 -0700, "art" wrote:
the Yagi put antenna design back by over half a century What a curious statement. The Yagi was invented when the science of antennas was barely 20 years along. By art's accuracy in perverse ungineering, the Yagi threw us back into the era of wired telegraphy and semaphore. Anyone want to ruminate on the absurdities of watching "I love Lucy" reruns through Western Union telegrams? Flip through 525 quickly to see one frame, but don't look at the bill at the commercial break! ;-) 73's Richard Clark, KB7QHC |
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