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Causes of Distrust of NEC and Mininec programs
Cebic found when comparing different style programs that some behaved
well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them |
Causes of Distrust of NEC and Mininec programs
On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin
wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them How do I simulate a sheet metal or other metal structure in NEC, when the software only knows (infinitesimally thin) "wires" w. |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 6:23*am, Art Unwin wrote:
Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them the key is that while all the programs are based on maxwell's equations, it is impossible to implement maxwell's equations with 100% accuracy on a digital computer. this is true of any and all simulation and modeling programs for electrical or mechanical design. all such programs make approximations and take shortcuts to reduce calculation time while maintaining some minimum level of accuracy and precision. it is important to understand the assumptions and simplifications that have been made in order to make proper use of the programs. typical traps in antenna simulations are that they don't like very small or very large length/diameter ratios... so using them for extrement long or short wires or very fat or very thin wires may produce results that aren't realistic. many of them also don't like very small spacing between wires, this is where most optimizer programs fall apart, they start moving wires close together and get strange results like super gain or unrealizable narrow beam patterns, often accompanied by a very low feedpoint impedance. most reputable programs like NEC have been validated very diligently over many years and their accuracy is well documented... as are the restrictions and assumptions that apply, but you have to read ALL the documentation, not just the quick start guide. Other programs like mininec, ao, yo, yagimax, and others make even more simplifications and therefore added restrictions so they can run on a desktop relatively quickly. unfortunately they don't always document the limitations as well as the professional level products. after all the professionals have millions of dollars riding on the accuracy of designs, hams have only pennies, so it just doesn't pay to write lots of documentation or do lots of testing that won't be read for ham users. so, while all the programs must be based on the same equations, the results they generate, especially in the fringe cases, may be vastly different. remember two maxims... 'garbage in - garbage out', and 'you get what you pay for'. |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 12:23*am, Art Unwin wrote:
*What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. "Figures in the order or 100%" of what? All radiators of all sizes and shapes will radiate on the order of 100% of all the r-f energy that can be coupled into them through their input terminals, whether or not those conductor sizes/shapes are naturally resonant at the applied frequency. But the fact remains that natural resonance does not occur in electrically small radiators -- while their radiation resistance is very small, and their feedpoint is very reactive. These realities make it very difficult to supply r-f power to such a radiator without relatively high losses. As a consequence, the efficiency of the transmitter SYSTEM (transmitter + radiator + matching network, + r-f ground loss in the case of monopoles) can be very low. To illustrate, the link below leads to a calculation of the performance of a 3-meter monopole system on 1500 kHz. Due to the low radiation resistance and system losses, and even though the short monopole itself is nearly 100% efficient at radiating the power across its feedpoint, that radiator receives only about 0.37% of the power available from the transmitter. So the system efficiency is very poor. Such an electrically short radiator (no matter what its shape) is not very useful compared to a naturally resonant 1/4-wave monopole or 1/2- wave dipole -- both of which can radiate nearly 100% of the available power. The calculations in the link below were made using standard equations, in a spreadsheet format to make it easy to follow and confirm. Properly constructed/used NEC models will verify the spreadsheet calculation, and the statements about the dipoles mentioned above. There is no cause to distrust NEC when it is properly understood and properly used. http://i62.photobucket.com/albums/h8...5on1500kHz.gif RF |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 1:16*am, Helmut Wabnig hwabnig@ .- --- -. dotat wrote:
On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * *The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! *If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them How do I simulate a sheet metal or other metal structure in NEC, when the software only knows (infinitesimally thin) "wires" w. For total accuracy you MUST take account of voltage overshoot which is neglected, so that something other than a "period:" of a cycle will provide repeatability of the half wave intersection with respect to resistance. Note, "infinitesimally" is not "finite", Maxwell's equation are of finite metrics and not close enough as in horse shoes! |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 6:18*am, Dave wrote:
On Nov 15, 6:23*am, Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them the key is that while all the programs are based on maxwell's equations, it is impossible to implement maxwell's equations with 100% accuracy on a digital computer. *this is true of any and all simulation and modeling programs for electrical or mechanical design. all such programs make approximations and take shortcuts to reduce calculation time while maintaining some minimum level of accuracy and precision. *it is important to understand the assumptions and simplifications that have been made in order to make proper use of the programs. *typical traps in antenna simulations are that they don't like very small or very large length/diameter ratios... so using them for extrement long or short wires or very fat or very thin wires may produce results that aren't realistic. *many of them also don't like very small spacing between wires, this is where most optimizer programs fall apart, they start moving wires close together and get strange results like super gain or unrealizable narrow beam patterns, often accompanied by a very low feedpoint impedance. most reputable programs like NEC have been validated very diligently over many years and their accuracy is well documented... as are the restrictions and assumptions that apply, but you have to read ALL the documentation, not just the quick start guide. *Other programs like mininec, ao, yo, yagimax, and others make even more simplifications and therefore added restrictions so they can run on a desktop relatively quickly. *unfortunately they don't always document the limitations as well as the professional level products. *after all the professionals have millions of dollars riding on the accuracy of designs, hams have only pennies, so it just doesn't pay to write lots of documentation or do lots of testing that won't be read for ham users. so, while all the programs must be based on the same equations, the results they generate, especially in the fringe cases, may be vastly different. *remember two maxims... 'garbage in - garbage out', and 'you get what you pay for'. Exactly. If one uses a "period" of a cycle or a full wave instead of fractional wavelengths Maxwell's equations can be used in antenna programs to achieve 100% accountability or efficiency Where as the fudge figure of fractional wavelengths can only achieve efficiencies in the lower 90s unless voltage over shoot is accounted for. Programs with optimizers recognize over shoot by providing radiators that are all multiples of a wavelength and resonant so that the array is also resonant as a whole. |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 6:47*am, Richard Fry wrote:
On Nov 15, 12:23*am, Art Unwin wrote: *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. "Figures in the order or 100%" of what? All radiators of all sizes and shapes will radiate on the order of 100% of all the r-f energy that can be coupled into them through their input terminals, whether or not those conductor sizes/shapes are naturally resonant at the applied frequency. But the fact remains that natural resonance does not occur in electrically small radiators -- while their radiation resistance is very small, and their feedpoint is very reactive. *These realities make it very difficult to supply r-f power to such a radiator without relatively high losses. As a consequence, the efficiency of the transmitter SYSTEM (transmitter + radiator + matching network, + r-f ground loss in the case of monopoles) can be very low. To illustrate, the link below leads to a calculation of the performance of a 3-meter monopole system on 1500 kHz. *Due to the low radiation resistance and system losses, and even though the short monopole itself is nearly 100% efficient at radiating the power across its feedpoint, that radiator receives only about 0.37% of the power available from the transmitter. *So the system efficiency is very poor. Such an electrically short radiator (no matter what its shape) is not very useful compared to a naturally resonant 1/4-wave monopole or 1/2- wave dipole -- both of which can radiate nearly The use of the term "nearly" does not imply total accuracy. To use Maxwell's equations for accuracy one cannot introduce metrics that are not absolute. 1/4 or 1/2 wave radiators cannot supplant the "period" of a wave form and thus introduce inaccuracies. The use of different algarithums in programing accentuate or minimise the effect of these inaccuracies thus providing different results. Same goes for close spaced wires where the use of "near" accurate capacitances by avoidance of all other proximety effects again take away from the accuracy of Maxwell's equations. An accurate measurement of resonance of a mesh as I have shown on my web page need not be dissed because of the presence of a computer program. 100% of the available power. The calculations in the link below were made using standard equations, in a spreadsheet format to make it easy to follow and confirm. Properly constructed/used NEC models will verify the spreadsheet calculation, and the statements about the dipoles mentioned above. There is no cause to distrust NEC when it is properly understood and properly used. http://i62.photobucket.com/albums/h8...5on1500kHz.gif RF |
Causes of Distrust of NEC and Mininec programs
Helmut Wabnig wrote:
How do I simulate a sheet metal or other metal structure in NEC, when the software only knows (infinitesimally thin) "wires" One creates a mesh using wires. The openings in the mesh must be small compared to a wavelength. Here's how I modeled my pickup - don't know how accurate it might be. http://www.w5dxp.com/SHOOTOUT.EZ -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 11:40*am, Cecil Moore wrote:
Helmut Wabnig wrote: How do I simulate a sheet metal or other metal structure in NEC, when the software only knows (infinitesimally thin) "wires" One creates a mesh using wires. The openings in the mesh must be small compared to a wavelength. Here's how I modeled my pickup - don't know how accurate it might be. http://www.w5dxp.com/SHOOTOUT.EZ -- 73, Cecil, IEEE, OOTC, *http://www.w5dxp.com Correct Cecil, note that you are refering to a wavelength and not a fractional WL This is the foundation of a Faraday cage which is the very essence of a passive radiator. In a mesh the current applied is straight but broken up into segments so that the displacement current is also broken up by encircling the holes. The holes consist of a capacitor or a field that when intersected by the initial current field produces acceleration to applied particles while within the confines of the intersection. This mechanism provides the maximum acceleration possible within the Universe per Einstein where the particle achieves the same properties as that exhibited by light and other non visible phenomina such as x rays etc |
Causes of Distrust of NEC and Mininec programs
Art Unwin wrote:
What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is resonant at exact and repeatable measurements. then Art wrote: The use of the term "nearly" does not imply total accuracy. Note that your use of the phrase "in the order of" does not imply total accuracy, either -- even for radiators meeting your criteria. To use Maxwell's equations for accuracy one cannot introduce metrics that are not absolute. 1/4 or 1/2 wave radiators cannot supplant the "period" of a wave form and thus introduce inaccuracies. Apparently you believe that only full-wave radiators are "perfect" (exactly 100% efficient). However a full-wave, center-fed dipole has a radiation resistance of about 2,000 ohms, and a feedpoint reactance exceeding 1,000 ohms (capacitive). That impedance would present a very high VSWR to a normal transmitter unless some kind of matching network was used. Even if there was no matching or transmission line loss (or r-f ground loss in the case of a monopole), that full-wave radiator still would not be 100% efficient because of the ohmic losses encountered by the r- f current flowing along the radiating structure (NOT the radiation resistance). RF |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 4:14*pm, Art Unwin wrote:
On Nov 15, 6:18*am, Dave wrote: On Nov 15, 6:23*am, Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them the key is that while all the programs are based on maxwell's equations, it is impossible to implement maxwell's equations with 100% accuracy on a digital computer. *this is true of any and all simulation and modeling programs for electrical or mechanical design. all such programs make approximations and take shortcuts to reduce calculation time while maintaining some minimum level of accuracy and precision. *it is important to understand the assumptions and simplifications that have been made in order to make proper use of the programs. *typical traps in antenna simulations are that they don't like very small or very large length/diameter ratios... so using them for extrement long or short wires or very fat or very thin wires may produce results that aren't realistic. *many of them also don't like very small spacing between wires, this is where most optimizer programs fall apart, they start moving wires close together and get strange results like super gain or unrealizable narrow beam patterns, often accompanied by a very low feedpoint impedance. most reputable programs like NEC have been validated very diligently over many years and their accuracy is well documented... as are the restrictions and assumptions that apply, but you have to read ALL the documentation, not just the quick start guide. *Other programs like mininec, ao, yo, yagimax, and others make even more simplifications and therefore added restrictions so they can run on a desktop relatively quickly. *unfortunately they don't always document the limitations as well as the professional level products. *after all the professionals have millions of dollars riding on the accuracy of designs, hams have only pennies, so it just doesn't pay to write lots of documentation or do lots of testing that won't be read for ham users. so, while all the programs must be based on the same equations, the results they generate, especially in the fringe cases, may be vastly different. *remember two maxims... 'garbage in - garbage out', and 'you get what you pay for'. Exactly. If one uses a "period" of a cycle or a full wave instead of fractional wavelengths Maxwell's equations can be used in antenna programs to achieve 100% accountability or efficiency Where as the fudge figure of fractional wavelengths can only achieve efficiencies in the lower 90s unless voltage over shoot is accounted for. Programs with optimizers recognize over shoot by providing radiators that are all multiples of a wavelength and resonant so that the array is also resonant as a whole.- Hide quoted text - - Show quoted text - what exactly is 'voltage overshoot' and why does it affect modeling programs? you can model an antenna without ever calculating a voltage. all that is needed is current, which is usually much easier to track. all voltages can be calculated from the current after the fact if needed for figuring insulation requirements. |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 12:59*pm, Dave wrote:
On Nov 15, 4:14*pm, Art Unwin wrote: On Nov 15, 6:18*am, Dave wrote: On Nov 15, 6:23*am, Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them the key is that while all the programs are based on maxwell's equations, it is impossible to implement maxwell's equations with 100% accuracy on a digital computer. *this is true of any and all simulation and modeling programs for electrical or mechanical design. all such programs make approximations and take shortcuts to reduce calculation time while maintaining some minimum level of accuracy and precision. *it is important to understand the assumptions and simplifications that have been made in order to make proper use of the programs. *typical traps in antenna simulations are that they don't like very small or very large length/diameter ratios... so using them for extrement long or short wires or very fat or very thin wires may produce results that aren't realistic. *many of them also don't like very small spacing between wires, this is where most optimizer programs fall apart, they start moving wires close together and get strange results like super gain or unrealizable narrow beam patterns, often accompanied by a very low feedpoint impedance. most reputable programs like NEC have been validated very diligently over many years and their accuracy is well documented... as are the restrictions and assumptions that apply, but you have to read ALL the documentation, not just the quick start guide. *Other programs like mininec, ao, yo, yagimax, and others make even more simplifications and therefore added restrictions so they can run on a desktop relatively quickly. *unfortunately they don't always document the limitations as well as the professional level products. *after all the professionals have millions of dollars riding on the accuracy of designs, hams have only pennies, so it just doesn't pay to write lots of documentation or do lots of testing that won't be read for ham users. so, while all the programs must be based on the same equations, the results they generate, especially in the fringe cases, may be vastly different. *remember two maxims... 'garbage in - garbage out', and 'you get what you pay for'. Exactly. If one uses a "period" of a cycle or a full wave instead of fractional wavelengths Maxwell's equations can be used in antenna programs to achieve 100% accountability or efficiency Where as the fudge figure of fractional wavelengths can only achieve efficiencies in the lower 90s unless voltage over shoot is accounted for. Programs with optimizers recognize over shoot by providing radiators that are all multiples of a wavelength and resonant so that the array is also resonant as a whole.- Hide quoted text - - Show quoted text - what exactly is 'voltage overshoot' and why does it affect modeling programs? *you can model an antenna without ever calculating a voltage. *all that is needed is current, which is usually much easier to track. *all voltages can be calculated from the current after the fact if needed for figuring insulation requirements. When a energy switching action occurs as with energy exchange between an inductance and a capacitance a transient spur of voltage is created beyond the point of balance or equilibrium of the circuit. Tho this is only momentary, it delays the return of energy back to the capacitance to a lesser time. The capacitor then returns the energy back to the inductance but with a lesser voltage which again creates a transient spike of a now lesser value than before, such that the amplitude of a balanced "loss less" circuit is lost to one that defines vibration which in the human ear also creates communication. (When delving into the mathematical laws of vibration where the amplitude change and the similarity to vibration can be readily be seen. Any way, it can be seen that with the amplitude of vibration is ever changing, so must the point where the amplitude is repeatable ie resonant, must also change. Yes, you can model anything without ever considering voltage when you choose to omit the presence of overshoot for easability over accuracy. Regards Art where the amplitude |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 12:29*pm, Richard Fry wrote:
Art Unwin wrote: What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is resonant at exact and repeatable measurements. then Art wrote: The use of the term "nearly" does not imply total accuracy. Note that your use of the phrase "in the order of" does not imply total accuracy, either -- even for radiators meeting your criteria. To use Maxwell's equations for accuracy one cannot introduce metrics that are not absolute. 1/4 or 1/2 wave radiators cannot supplant the "period" of a wave form and thus introduce inaccuracies. Apparently you believe that only full-wave radiators are "perfect" (exactly 100% efficient). Until antenna programs all of which are based om Maxwell's equations provide accountability of all forces involved to provide the 100% efficiency, as shown by the use of full wave radiators I have no other choice. It is as the catholic religeon teachings when it says "give me the child and I will give you the man." Its equivalent in education is to believe only what the professor tells you that is written in his books as it is he who determines who graduates or not. Many of the masters did not have a formal education such as Greene who had to justify from first principles himself to determine what was correct and what was not. After serving most of your years in life by adhering to the books it make no sense in changing from a follower to a reseacher when the past has satisfied your need. As with religeon faith will always overide the tenents of science, more so as you get older. However a full-wave, center-fed dipole has a radiation resistance of about 2,000 ohms, and a feedpoint reactance exceeding 1,000 ohms (capacitive). *That impedance would present a very high VSWR to a normal transmitter unless some kind of matching network was used. Even if there was no matching or transmission line loss (or r-f ground loss in the case of a monopole), that full-wave radiator still would not be 100% efficient because of the ohmic losses encountered by the r- f current flowing along the radiating structure (NOT the radiation resistance). RF |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 8:10*pm, Art Unwin wrote:
On Nov 15, 12:59*pm, Dave wrote: On Nov 15, 4:14*pm, Art Unwin wrote: On Nov 15, 6:18*am, Dave wrote: On Nov 15, 6:23*am, Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them the key is that while all the programs are based on maxwell's equations, it is impossible to implement maxwell's equations with 100% accuracy on a digital computer. *this is true of any and all simulation and modeling programs for electrical or mechanical design. |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 1:23*am, Art Unwin wrote:
Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them How about giving some pointers as to where you got this BS. Sounds like you just made a bunch of stuff up. Jimmie |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 3:44*pm, JIMMIE wrote:
On Nov 15, 1:23*am, Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them How about giving some pointers as to where you got this BS. Sounds like you just made a bunch of stuff up. Jimmie No Jim. Ideas with what is presented to me in science, where such can be obtained from first principles and with agreement with known LAWS of science rather than various theories. In this case the aproach of Gauss provided a mathematical connection to Maxwells equations which by the use of antenna programs based on Maxwell only provide accountability of all forces. This is easily proven when use of a program that is optimized to account for all forces involved in radiation such that the solution provided is termed 100% efficient as opposed to planar or other designs that cannot achieve 100% efficiency because of the non accountability of the recognition of "over shoot". One always looks for 100% accountability of all forces such that 100% efficiency is achieved. If you are in the early stages of education it would be folly to bring forth suggestions to the contrary of those presented in the books and your professor since these are the standards against which determines whether you graduate or not. Obviously this is not the time to debate differences. As life proceedes one becomes comfortable with alignment with ideas and teachings that conform with those around you because in general your wages depend on it. Thus you are dealing with faith regardless of the attainment via first principles that produce conflict. So yes, your only response to continue a science debate is to provide counter proof from first principles that is available some where in a book! Compared to that task it is so much more convenient to exit the debate on a statement that does not require a proof. Thus anger comes to the fore and debate or a thread comes to an end. Cheers Art |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 3:00*pm, Dave wrote:
On Nov 15, 8:10*pm, Art Unwin wrote: On Nov 15, 12:59*pm, Dave wrote: On Nov 15, 4:14*pm, Art Unwin wrote: On Nov 15, 6:18*am, Dave wrote: On Nov 15, 6:23*am, Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. Yet all antenna programs are based on the use of Maxwells equations where all programs should have the same results, after all Maxwells equations are exact and not fudged. One of the reasons is that since Maxwells laws are exact radiators used must be resonant at repeatable points designated as a period. * *Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. * * The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! * If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. * *If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! *What one gains from this aproach is that any radiator of any shape, *size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them the key is that while all the programs are based on maxwell's equations, it is impossible to implement maxwell's equations with 100% accuracy on a digital computer. *this is true of any and all simulation and modeling programs for electrical or mechanical design. all such programs make approximations and take shortcuts to reduce calculation time while maintaining some minimum level of accuracy and precision. *it is important to understand the assumptions and simplifications that have been made in order to make proper use of the programs. *typical traps in antenna simulations are that they don't like very small or very large length/diameter ratios... so using them for extrement long or short wires or very fat or very thin wires may produce results that aren't realistic. *many of them also don't like very small spacing between wires, this is where most optimizer programs fall apart, they start moving wires close together and get strange results like super gain or unrealizable narrow beam patterns, often accompanied by a very low feedpoint impedance. most reputable programs like NEC have been validated very diligently over many years and their accuracy is well documented... as are the restrictions and assumptions that apply, but you have to read ALL the documentation, not just the quick start guide. *Other programs like mininec, ao, yo, yagimax, and others make even more simplifications and therefore added restrictions so they can run on a desktop relatively quickly. *unfortunately they don't always document the limitations as well as the professional level products. *after all the professionals have millions of dollars riding on the accuracy of designs, hams have only pennies, so it just doesn't pay to write lots of documentation or do lots of testing that won't be read for ham users. so, while all the programs must be based on the same equations, the results they generate, especially in the fringe cases, may be vastly different. *remember two maxims... 'garbage in - garbage out', and 'you get what you pay for'. Exactly. If one uses a "period" of a cycle or a full wave instead of fractional wavelengths Maxwell's equations can be used in antenna programs to achieve 100% accountability or efficiency Where as the fudge figure of fractional wavelengths can only achieve efficiencies in the lower 90s unless voltage over shoot is accounted for. Programs with optimizers recognize over shoot by providing radiators that are all multiples of a wavelength and resonant so that the array is also resonant as a whole.- Hide quoted text - - Show quoted text - what exactly is 'voltage overshoot' and why does it affect modeling programs? *you can model an antenna without ever calculating a voltage. *all that is needed is current, which is usually much easier to track. *all voltages can be calculated from the current after the fact if needed for figuring insulation requirements. When a energy switching action occurs as with energy exchange between an inductance and a capacitance a transient spur of voltage is created beyond the point of balance or equilibrium of the circuit. Tho this is only momentary, it delays the return of energy back to the capacitance to a lesser time. The capacitor then returns the energy back to the inductance but with a lesser voltage which again creates a transient spike of a now lesser value than before, such that the amplitude of a balanced "loss less" circuit is lost to one that defines vibration which in the human ear also creates communication. (When delving into the mathematical laws of vibration where the amplitude change and the similarity to vibration can be readily be seen. * Any way, it can be seen that with the amplitude of vibration is ever changing, so must the point where the amplitude is repeatable *ie resonant, must also change. Yes, you can model anything without ever considering voltage when you choose to omit the presence of overshoot for easability over accuracy. Regards Art where the amplitude- Hide quoted text - - Show quoted text - yeah, whatever you have been smoking is spiked with something. *LC resonant circuits do not have 'spikes', they have nice sinusoidal energy transfer... maybe you envision the electrons sloshsing back and forth like that swill in your glass? *sorry, it just don't work that way. *enjoy your own little world, it just got one person smaller. Well David prove it based on science instead of expecting me to accept you on faith. That is only accomplished by the source providing replacement such that consistent amplitude is maintained. Without this replacement the amplitude will show degradement as seen with vibration or a simple pendulum clock that exhibits the two vectors previously mentioned ie one linear and one circircular. There is no free lunch as with perpetual motion when equilibrium is broken. Cheers Art |
Causes of Distrust of NEC and Mininec programs
On Nov 15, Art Unwin wrote:
As with religeon [sic] faith will always overide [sic] the tenents [sic] of science, more so as you get older. then Well David prove it based on science instead of expecting me to accept you on faith. _____________ Art, you are the Master here at asking the readers of your posts to accept them on faith, while having provided no scientific proof for your posts whatsoever -- and while denying or at least ignoring the validity of other posts containing provable scientific and experiential evidence to the contrary. Why should any well-educated person accept _your_ faith-based, and unproven beliefs? RF |
Causes of Distrust of NEC and Mininec programs
On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin
wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. True. When circumstances dictate that I pay attention and I'm in a good mood, most programs behave normally. However, when circumstances are not so favorable, such as last week when I replaced my septic tank, all of the software I was using literally stunk. Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. Last time I checked, the definition of a half wave automagically includes any external or magical factors that might change its length. For example, if you submerge the antenna under water, the increased dielectric constant will cause the half wave length to somewhat shorten. While the previous length has changed, the new shorter length is still a half wavelength. The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Overshoot can easily be fixed with a Cutts Compensator. http://en.wikipedia.org/wiki/Cutts_compensator Every time you cycle your antenna, the recoil tends to make the barrel climb a bit. This is the cause of the overshoot. A suitable Cutts Compensator attached opposite the feed point should help prevent overshooting the target. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! 95.718% of all statistics are wrong. If you're using single digit accuracy and single digit significant figures, 92% rounded off is equal to 100%. If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. Half wave wire dipoles do tend to be resonant somewhat shorter than the free space wavelength. That's due to sales and value added tax placed on antennas by the government. You'll always come out a bit short when dealing with them. However, the last time I checked, the cut length was only about 5% shorter than the free space half-wave length. Did the antenna tax increase to 8%? If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! My antennas are exact and repeatable. Not only that, I can also repeat my mistakes every time. What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is resonant at exact and repeatable measurements. Perhaps. If you buy your antennas out of state or on eBay, you can avoid paying the 5% antenna length tax. However, you are required to pay Use Tax on any out of state purchases where the vendor neglected to collect the antenna tax and forward it to the Calif Franchise Tax Bored: http://www.ftb.ca.gov/current/usetax.shtml If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. Anyway, the problem is easily solved. Just increase your AC power line voltage about 5% and your numbers should increase by the same amount. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 5:49*pm, Jeff Liebermann wrote:
On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: Cebic found when comparing different style programs that some behaved well in certain circumstance where others did not. True. *When circumstances dictate that I pay attention and I'm in a good mood, most programs behave normally. *However, when circumstances are not so favorable, such as last week when I replaced my septic tank, all of the software I was using literally stunk. Fact is that most users use fractional wavelength designs, usually a half wavelength, that is not resonant at repeatable points where the area around the datum line of a sine wave is never equal when generated around a tank circuit. Last time I checked, the definition of a half wave automagically includes any external or magical factors that might change its length. For example, if you submerge the antenna under water, the increased dielectric constant will cause the half wave length to somewhat shorten. *While the previous length has changed, the new shorter length is still a half wavelength. Very true, but the measured length is never repeatable. Only at the point of a period is where it is repeatable which is how a cycle comes into being. The reason for this is "voltage over shoot" which gets smaller with every cycle but never disappears. Overshoot can easily be fixed with a Cutts Compensator. http://en.wikipedia.org/wiki/Cutts_compensator Ofshoot can be essentially removed or minimised by just the addition of a resister but such methods are not included in antenna computer programs. Every time you cycle your antenna, the recoil tends to make the barrel climb a bit. *This is the cause of the overshoot. *A suitable Cutts Compensator attached opposite the feed point should help prevent overshooting the target. Thus when programs are used based on fractional wavelength radiators the results will never show 100% accountability and in fact efficiencies derived will be in the order of 92%! 95.718% of all statistics are wrong. *If you're using single digit accuracy and single digit significant figures, 92% rounded off is equal to 100%. Again what ever trips your trigger, horse shoes or Maxwells equations. Only when accurate metrics are inserted in a program can the accuracy of Maxwell's equations be shown and the half wave length can never be stated accurately. If the radiator is of a wavelength then one is not using a "fudge" figure in the calculations and *then becomes possible to attain total accountability with efficiency of 100%. regardles of what type program is used. Half wave wire dipoles do tend to be resonant somewhat shorter than the free space wavelength. *That's due to sales and value added tax placed on antennas by the government. *You'll always come out a bit short when dealing with them. *However, the last time I checked, the cut length was only about 5% shorter than the free space half-wave length. *Did the antenna tax increase to 8%? If one is to use exact equations, as are Maxwell equations, then one must also use measurements that are also exact and repeatable and that is definitely not fractional wavelengths! My antennas are exact and repeatable. *Not only that, I can also repeat my mistakes every time. Yes you have shown evidence of that. What one gains from this aproach is that any radiator of any shape, size or elevation can provide figures in the order of 100% as long as the radiator is a multiple of a wavelength where it is *resonant at exact and repeatable measurements. Perhaps. *If you buy your antennas out of state or on eBay, you can avoid paying the 5% antenna length tax. *However, you are required to pay Use Tax on any out of state purchases where the vendor neglected to collect the antenna tax and forward it to the Calif Franchise Tax Bored: http://www.ftb.ca.gov/current/usetax.shtml If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? *You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. *For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. Anyway, the problem is easily solved. *Just increase your AC power line voltage about 5% and your numbers should increase by the same amount. Maybe true but physics demands accuracy which explains the heavy useage of constant added to justify the use of an equal sign. Same thing goes for the myriad of particles invented that are not seen or measurable. This because those who delve in physics sometimes replace a constant with a new invented particle that can substantiate equilibrium or its cousin "equal" -- Jeff Liebermann * * You know, a well known former ham Stephen Best got hold of a new antenna program that had strict adherence to Maxwells laws. The program relied on Poynting circle as being representitive for all forces in radiation. The program ,probably more than I can afford. produced a radiator that was not straight according to the old wives tale that is propagated by hams. It showed something like a tennis ball where multiple wavelengths of radiator were stuffed inside and where balance or equilibrium was obtained. In his study which was around a half wave radiater produced a radiation pattern that was a perfect hemisphere that all on this group stated was impossible to attain. ( actually it was based on a full wave where the ground plane supplied the mirror image) Possibly in our time, that will make it into the newer physics books, that will force the re thinking of radiation. This paper is on the WWW but I leave it to you to show that it must be in error as it is not yet in the books! At the same time opponents will bring forwards Toms adage W8TI, that for maximum efficiency a radiator must be straight, thus leaving him with the onus of showing that Steven Best efforts were all wrong by the use of the soon to be corrected theory corrections before old theories are fully discounted where all may read it for themselves in a book. Art Art 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-2558 |
Causes of Distrust of NEC and Mininec programs
Art Unwin wrote:
On Nov 15, 3:00 pm, Dave wrote:- yeah, whatever you have been smoking is spiked with something. LC resonant circuits do not have 'spikes', they have nice sinusoidal energy transfer... maybe you envision the electrons sloshsing back and forth like that swill in your glass? sorry, it just don't work that way. enjoy your own little world, it just got one person smaller. Well David prove it based on science instead of expecting me to accept you on faith. That is only accomplished by the source providing replacement such that consistent amplitude is maintained. Without this replacement the amplitude will show degradement as seen with vibration or a simple pendulum clock that exhibits the two vectors previously mentioned ie one linear and one circircular. There is no free lunch as with perpetual motion when equilibrium is broken. Cheers Art Art You ask others to prove things based on science while you ignore proven and demonstrable science and make up your own "facts". You have never proven or demonstrated ANYTHING, yet have the frigging balls to require others to do so. A hypocrite by any other name is still a hypocrite. tom K0TAR |
Causes of Distrust of NEC and Mininec programs
JIMMIE wrote:
On Nov 15, 1:23 am, Art Unwin wrote: snip lots of BULLSH*T How about giving some pointers as to where you got this BS. Sounds like you just made a bunch of stuff up. Jimmie Exactly right. He makes it all up. It's easy to tell if you read him long enough, because his story is continuously changing. When you stick to the truth or reality that doesn't happen. tom K0TAR |
Causes of Distrust of NEC and Mininec programs
Jeff Liebermann wrote:
On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: snip lots of CRAP If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. snip a bit And anytime anyone does respond with a credible argument, he makes up new "facts" to cover his ass. tom K0TAR |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 7:16*pm, tom wrote:
Jeff Liebermann wrote: On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: snip lots of CRAP If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? *You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. *For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. snip a bit And anytime anyone does respond with a credible argument, he makes up new "facts" to cover his ass. tom K0TAR I do not have to prove anything to you! The first project is to obtain a patent that is desired by those skilled in the art of making money on new antenna disclosures. You have neither of those requirements. Because you are unarmed with respect to having skill in the science of antennas it is normal to gravitate towards insults where the record shows that your knowledge of antennas is negligeable. It is impossible to debate science with one that excells only with the skill of memory that parrots only that which can be memorised by a reading of a book with zero understanding. Ofcourse, if you had a tangible record on the teachings on the science of antennas you surely would have provided evidence of same, rather than the use of slander to provide perceived elevation of your station in the presence of Madame Guillotine, where the loudest voice becomes a leader of what is just a mob. I have never seen evidence in your postings that you have had a tangible trail of education that would substantiate your self perceived expertise in the field of antennas thus you do not have a real beef to show on this thread. As for your statement "as for all I know" it is better that you believe in magic where faith overcomes physics. |
Causes of Distrust of NEC and Mininec programs
Art Unwin wrote:
On Nov 15, 7:16 pm, tom wrote: Jeff Liebermann wrote: On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: snip lots of CRAP If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. snip a bit And anytime anyone does respond with a credible argument, he makes up new "facts" to cover his ass. tom K0TAR I do not have to prove anything to you! The first project is to obtain a patent that is desired by those skilled in the art of making money on new antenna disclosures. You have neither of those requirements. Because you are unarmed with respect to having skill in the science of antennas it is normal to gravitate towards insults where the record shows that your knowledge of antennas is negligeable. It is impossible to debate science with one that excells only with the skill of memory that parrots only that which can be memorised by a reading of a book with zero understanding. Ofcourse, if you had a tangible record on the teachings on the science of antennas you surely would have provided evidence of same, rather than the use of slander to provide perceived elevation of your station in the presence of Madame Guillotine, where the loudest voice becomes a leader of what is just a mob. I have never seen evidence in your postings that you have had a tangible trail of education that would substantiate your self perceived expertise in the field of antennas thus you do not have a real beef to show on this thread. As for your statement "as for all I know" it is better that you believe in magic where faith overcomes physics. And who has paid for use of your patents? And how much? I am sure we all know the answer. No one, and nothing. My antenna designs are actually being used very successfully, and yours aren't. You are a fraud and a hypocrite. tom K0TAR |
Causes of Distrust of NEC and Mininec programs
Art Unwin wrote:
On Nov 15, 7:16 pm, tom wrote: Jeff Liebermann wrote: On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: snip lots of CRAP If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. snip a bit And anytime anyone does respond with a credible argument, he makes up new "facts" to cover his ass. tom K0TAR I do not have to prove anything to you! The first project is to obtain a patent that is desired by those skilled in the art of making money on new antenna disclosures. You have neither of those requirements. Because you are unarmed with respect to having skill in the science of antennas it is normal to gravitate towards insults where the record shows that your knowledge of antennas is negligeable. It is impossible to debate science with one that excells only with the skill of memory that parrots only that which can be memorised by a reading of a book with zero understanding. Ofcourse, if you had a tangible record on the teachings on the science of antennas you surely would have provided evidence of same, rather than the use of slander to provide perceived elevation of your station in the presence of Madame Guillotine, where the loudest voice becomes a leader of what is just a mob. I have never seen evidence in your postings that you have had a tangible trail of education that would substantiate your self perceived expertise in the field of antennas thus you do not have a real beef to show on this thread. As for your statement "as for all I know" it is better that you believe in magic where faith overcomes physics. Where did I say "as for all I know"? Making stuff up again. Big surprise. Fraud, hypocrite, and confirmed liar. tom K0TAR |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 8:57*pm, tom wrote:
Art Unwin wrote: On Nov 15, 7:16 pm, tom wrote: Jeff Liebermann wrote: On Sat, 14 Nov 2009 22:23:05 -0800 (PST), Art Unwin wrote: snip lots of CRAP If anybody can give pointers that refute the accuracy of the above I would be very interested in hearing them Why? *You haven't proven your point, demonstrated the phenomenon, or otherwise provided anything worth tearing apart. *For all I know, your antennas are shorter than expected because of magic, enchantment, sloppy construction, mis-measurement, or all the aforementioned. snip a bit And anytime anyone does respond with a credible argument, he makes up new "facts" to cover his ass. tom K0TAR I do not have to prove anything to you! The first project is to obtain a patent that is desired by those skilled in the art of making money on new antenna disclosures. You have neither of those requirements. Because you are unarmed with respect to having skill in the science of antennas it is normal to gravitate towards insults where the record shows that your knowledge of antennas is negligeable. It is impossible to debate science with one that excells only with the skill of memory that parrots only that which can be memorised by a reading of a book with zero understanding. Ofcourse, if you had a tangible record on the teachings on the science of antennas you surely would have provided evidence of same, rather than the use of slander to provide perceived elevation of your station in the presence of Madame Guillotine, *where the loudest voice becomes a leader of what is just a mob. I have never seen evidence in your postings that you have had a tangible trail of education that would substantiate your self perceived expertise in the field of antennas thus you do not have a real beef to show on this thread. As for your statement "as for all I know" it is better that you believe in magic where faith overcomes physics. And who has paid for use of your patents? *And how much? *I am sure we all know the answer. *No one, and nothing. My antenna designs are actually being used very successfully, and yours aren't. You are a fraud and a hypocrite. tom K0TAR So you are a millionare today? Patent number? The present industry is advocating the invention of a new science with respect to obtaining smaller radiators. Get in there and double your money while the consortium continue to struggle with the design of a new technology.alternative than that supplied by nature. If you had such knowledge you would not be persueing insults in place of debate. |
Causes of Distrust of NEC and Mininec programs
Art Unwin wrote:
My antenna designs are actually being used very successfully, and yours aren't. You are a fraud and a hypocrite. tom K0TAR So you are a millionare today? Patent number? The present industry is advocating the invention of a new science with respect to obtaining smaller radiators. Get in there and double your money while the consortium continue to struggle with the design of a new technology.alternative than that supplied by nature. If you had such knowledge you would not be persueing insults in place of debate. I'm not claiming or implying (as you are) that I'm making money on anything. Just that my antennas are actually used by real people quite successfully. And given what you've been saying to anyone that responds to you, you have no place to stand on insults since you are great at supplying multiple paragraphs of them at a time. At least mine are pertinent to the subject. I have no interest in small antennas or making money on them. I am however interested in the truth and antennas that truly work. And you are interested in BS and self promotion. Have fun with your fraud, hypocrisy and lies. And try to learn to spell. tom K0TAR |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 10:17*pm, Art Unwin wrote:
. Sounds like you just made a bunch of stuff up. Jimmie No Jim. Ideas with what is presented to me in science, where *such can be obtained from first principles and with agreement with known LAWS of science rather than various theories. Is scientific theory inferior to scientific laws? |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 9:34*pm, Bill wrote:
On Nov 15, 10:17*pm, Art Unwin wrote: *. Sounds like you just made a bunch of stuff up. Jimmie No Jim. Ideas with what is presented to me in science, where *such can be obtained from first principles and with agreement with known LAWS of science rather than various theories. Is scientific theory inferior to scientific laws? Yes |
Causes of Distrust of NEC and Mininec programs
On Sun, 15 Nov 2009 17:00:10 -0800 (PST), Art Unwin
wrote: Very true, but the measured length is never repeatable. Only at the point of a period is where it is repeatable which is how a cycle comes into being. One cycle = one period = one wavelength Do you have a problem with this? Ofshoot can be essentially removed or minimised by just the addition of a resister but such methods are not included in antenna computer programs. Adding a resistor will increase the resonant length of an antenna by 5% to 8%. Amazing. I didn't know that. Since resonance is where the inductive and cazapative reactances cancel, leaving only the real part of the antenna impedance, I would think that adding a resistor anywhere would have no effect on the reactive components. Again what ever trips your trigger, horse shoes or Maxwells equations. When I was younger, it was sex, drugs, and rock and roll. These days it's pills, politics, and entertainment value that keeps me going. Only when accurate metrics are inserted in a program can the accuracy of Maxwell's equations be shown and the half wave length can never be stated accurately. How accurately would you like them to be stated? 1%? 0.1%? 0.00000001% Accuracy is usually expressed with numbers. I fail to see any numbers. There's also a question of what's "good enough". Infinite resolution and accuracy doesn't do me much good if the operating bandwidth of the antenna is substantial, or the operating requirements of system are rather minimal. My antennas are exact and repeatable. *Not only that, I can also repeat my mistakes every time. Yes you have shown evidence of that. To err is human. Reassurances are not required. For my mistakes, I'll accept responsibility but not blame. Two wrongs don't make a right, but do eliminate two possibilities, thus eventually leading to the right answer. Positive feedback is inherently unstable. One does not learn by getting positive acclamation and praise. One learns from negative feedback which is inherently stable and a much more effective learning experience. Maybe true but physics demands accuracy Physics does not demand accuracy. However, my customers might. which explains the heavy useage of constant added to justify the use of an equal sign. None of my work is linear. Therefore constants added as fudge, finagle, or tweak factors are useless. I prefer to multiple my results in order to conjure the correct answer. Same thing goes for the myriad of particles invented that are not seen or measurable. Yep. I suck them up in my vacuum cleaner when they start to become measurable. This because those who delve in physics sometimes replace a constant with a new invented particle that can substantiate equilibrium or its cousin "equal" I'll look in the vacuum cleaner bag next time I have a chance for any new particles. You know, a well known former ham Stephen Best got hold of a new antenna program that had strict adherence to Maxwells laws. The program relied on Poynting circle as being representitive for all forces in radiation. The program ,probably more than I can afford. produced a radiator that was not straight according to the old wives tale that is propagated by hams. It showed something like a tennis ball where multiple wavelengths of radiator were stuffed inside and where balance or equilibrium was obtained. In his study which was around a half wave radiater produced a radiation pattern that was a perfect hemisphere that all on this group stated was impossible to attain. ( actually it was based on a full wave where the ground plane supplied the mirror image) Possibly in our time, that will make it into the newer physics books, that will force the re thinking of radiation. This paper is on the WWW but I leave it to you to show that it must be in error as it is not yet in the books! I think you mean this: http://www.cst.com/Content/Applications/Article/A+Small,+Efficient,+Linear-polarized+Omni-directional+Antenna I've been trying to understand it for some time. Again, it's not my place to find your errors. It's your place to prove and demonstrate your allegations. At the same time opponents will bring forwards Toms adage W8TI, that for maximum efficiency a radiator must be straight, thus leaving him with the onus of showing that Steven Best efforts were all wrong by the use of the soon to be corrected theory corrections before old theories are fully discounted where all may read it for themselves in a book. Dr Best didn't seem to mention anything about the design being any more efficient than a larger antenna. He had a design requirement to fit an antenna inside a 0.04 wavelength diameter ball, and optimized his design around that requirement. Getting 1.6dBi of gain out such a small antenna is impressive. Incidentally, his design is NOT a half-hemisphere. He uses the symmetry of the antenna to dramatically reduce his calculation time. Yes, there are some things that NEC doesn't so very well, or rather other programs do much better. For example, for microstrip and slot antennas, I'm trying to learn Mstrip40: http://www.spl.ch/software/MultiSTRIP/Manual.htm when not posting inane drive to Usenet. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 9:50*pm, Jeff Liebermann wrote:
On Sun, 15 Nov 2009 17:00:10 -0800 (PST), Art Unwin wrote: Very true, but the measured *length is never repeatable. Only at the point of a period is where it is repeatable which is how a cycle comes into being. One cycle = one period = one wavelength Do you have a problem with this? Ok jeff your turn wih aiming the cannon. No ofcourse not, as long as the cycle is complete and terminates and terminates at the point designated as the period. Good enough ? Ofshoot can be essentially removed or minimised by just the addition of a resister but such methods are not included in antenna computer programs. Adding a resistor will increase the resonant length of an antenna by 5% to 8%. *Amazing. *I didn't know that. *Since resonance is where the inductive and cazapative reactances cancel, leaving only the real part of the antenna impedance, I would think that adding a resistor anywhere would have no effect on the reactive components. Again what ever trips your trigger, horse shoes or Maxwells equations. When I was younger, it was sex, drugs, and rock and roll. *These days it's pills, politics, and entertainment value that keeps me going. Only when accurate metrics are inserted in a program can the accuracy of Maxwell's equations be shown and the half wave length can never be stated accurately. How accurately would you like them to be stated? * 1%? *0.1%? 0.00000001% Enough according to my needs. If the needs are expanded then their is no point in expanding errors implanted for past convenience. O.K ? Accuracy is usually expressed with numbers. *I fail to see any numbers. *There's also a question of what's "good enough". *Infinite resolution and accuracy doesn't do me much good if the operating bandwidth of the antenna is substantial, or the operating requirements of system are rather minimal. very true as your needs are minimal OK ? My antennas are exact and repeatable. *Not only that, I can also repeat my mistakes every time. Hmm I wont bite at that bait OK? Yes you have shown evidence of that. To err is human. *Reassurances are not required. For my mistakes, I'll accept responsibility but not blame. Again very understandable Two wrongs don't make a right, but do eliminate two possibilities, thus eventually leading to the right answer. Quite true. Only one who has experienced many bankrupcys has the necessary wisdom to become rich The wisdom is usually at the expense of others OK? Positive feedback is inherently unstable. Why do you think that? *One does not learn by getting positive acclamation and praise. *One learns from negative feedback which is inherently stable and a much more effective learning experience. I believe my answer with respect to attaining wisdom is a suitable response for that! Maybe true but physics demands accuracy Exactly where space for a constant is provided as learning improves. Physics does not demand accuracy. *However, my customers might. Might is a untangible. If one wants to expand on the design of smaller antennas one does not pursue a fudge factor which suggests that the smallest of smallest of radiators will also meet ones needs. That is like adding height to buildings built on sand instead of first ataining a sound foundation in advance of any expansion which explains the heavy useage of constant added to justify the use of an equal sign. None of my work is linear. *Therefore constants added as fudge, finagle, or tweak factors are useless. *I prefer to multiple my results in order to conjure the correct answer. Same thing goes for the myriad of particles invented that are not seen or measurable. Yep. *I suck them up in my vacuum cleaner when they start to become measurable. Well physics point to a difference in pressures on a carpet from that attained by that which provides a suction. This because those who delve in physics sometimes replace a constant with a new invented particle that can substantiate equilibrium or its cousin "equal" I'll look in the vacuum cleaner bag next time I have a chance for any new particles. Well an "equal" sign in mathematics designates balance on both sides of the sign. Was it the arabs that expanded the term to equilibrium that could accompany the use of boundary laws? You know, *a well known former ham Stephen Best got hold of a new antenna program that had strict adherence to Maxwells laws. The program relied on Poynting circle as being representitive * for all forces in radiation. The program ,probably more than I can afford. produced a radiator that was not straight according to the old wives tale that is propagated by hams. It showed something like a tennis ball where multiple wavelengths of radiator were stuffed inside and where balance or equilibrium was obtained. In his study which was around a half wave radiater produced a radiation pattern that was a perfect hemisphere that all on this group stated was impossible to attain. ( actually it was based on a full wave where the ground plane supplied the mirror image) Possibly in our time, that will make it into the newer physics books, that will force the re thinking of radiation. This paper is on the WWW but I leave it to you to show that it must be in error as it is not yet in the books! I think you mean this: http://www.cst.com/Content/Applications/Article/A+Small,+Efficient,+L... I've been trying to understand it for some time. I dont recognise that as time has passed by. Again, it's not my place to find your errors. *It's your place to prove and demonstrate your allegations. That cannot be done when others rely on theories because they are seen written in a book. It takes corroberation with existing laws to supply a modicom of science teachings where those agreements can then be built upon. This is a repeat of the battles of faith versus the observations and deductions provided by science. At the same time opponents will bring forwards Toms adage W8TI, that for maximum efficiency a radiator must be straight, thus leaving him with the onus of showing that Steven Best efforts were all wrong by the use of the soon to be corrected theory corrections before old theories are fully discounted where all may read it for themselves in *a book. Dr Best didn't seem to mention anything about the design being any more efficient than a larger antenna. *He had a design requirement to fit an antenna inside a 0.04 wavelength diameter ball, and optimized his design around that requirement. *Getting 1.6dBi of gain out such a small antenna is impressive. Yes, but more important was the ability to stuff wavelengths of radiator showing past erronius suggestion that a radiator must be straight.On top of that he attained a hemisperical radiation pattern that this group stated was impoissible. Thus another false old wives tale was debunked, By the way the paper in no way suggested a "electrically" small antenna, only a "physically" smaller antenna, so you need to re read the paper. Incidentally, his design is NOT a half-hemisphere. *He uses the symmetry of the antenna to dramatically reduce his calculation time. Yes, there are some things that NEC doesn't so very well, or rather other programs do much better. I have stated same *For example, for microstrip and slot antennas, I'm trying to learn Mstrip40: http://www.spl.ch/software/MultiSTRIP/Manual.htm when not posting inane drive to Usenet. Then you are a better man than I Gunga Din. It was the very interpretation of the phenomina of a slot antenna that led to confrontation with the idea of particles as the carriers of radiation. Perhaps you can find errors in that assertation which is so much less difficult in convincing same to those who abide purely on faith. Phew, that was a long questionaire but as always my life and thoughts is an open book. I hope the above satisfies your needs! -- Jeff Liebermann * * 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-2558 |
Causes of Distrust of NEC and Mininec programs
Helmut Wabnig wrote:
How do I simulate a sheet metal or other metal structure in NEC, when the software only knows (infinitesimally thin) "wires" w. You simulate it as a wire grid, like a screen. Download the free EZNEC demo program, or just the manual, from http://eznec.com, and look in the index under "Wire Grid Modeling" for more information. This technique is widely used and generally gives very good results. Roy Lewallen, W7EL |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 10:50*pm, Jeff Liebermann wrote:
On Sun, 15 Nov 2009 17:00:10 -0800 (PST), Art Unwin wrote: Very true, but the measured *length is never repeatable. Only at the point of a period is where it is repeatable which is how a cycle comes into being. One cycle = one period = one wavelength Do you have a problem with this? Ofshoot can be essentially removed or minimised by just the addition of a resister but such methods are not included in antenna computer programs. Adding a resistor will increase the resonant length of an antenna by 5% to 8%. *Amazing. *I didn't know that. *Since resonance is where the inductive and cazapative reactances cancel, leaving only the real part of the antenna impedance, I would think that adding a resistor anywhere would have no effect on the reactive components. Again what ever trips your trigger, horse shoes or Maxwells equations. When I was younger, it was sex, drugs, and rock and roll. *These days it's pills, politics, and entertainment value that keeps me going. Only when accurate metrics are inserted in a program can the accuracy of Maxwell's equations be shown and the half wave length can never be stated accurately. How accurately would you like them to be stated? * 1%? *0.1%? 0.00000001% Accuracy is usually expressed with numbers. *I fail to see any numbers. *There's also a question of what's "good enough". *Infinite resolution and accuracy doesn't do me much good if the operating bandwidth of the antenna is substantial, or the operating requirements of system are rather minimal. My antennas are exact and repeatable. *Not only that, I can also repeat my mistakes every time. Yes you have shown evidence of that. To err is human. *Reassurances are not required. For my mistakes, I'll accept responsibility but not blame. Two wrongs don't make a right, but do eliminate two possibilities, thus eventually leading to the right answer. Positive feedback is inherently unstable. *One does not learn by getting positive acclamation and praise. *One learns from negative feedback which is inherently stable and a much more effective learning experience. Maybe true but physics demands accuracy Physics does not demand accuracy. *However, my customers might. which explains the heavy useage of constant added to justify the use of an equal sign. None of my work is linear. *Therefore constants added as fudge, finagle, or tweak factors are useless. *I prefer to multiple my results in order to conjure the correct answer. Same thing goes for the myriad of particles invented that are not seen or measurable. Yep. *I suck them up in my vacuum cleaner when they start to become measurable. This because those who delve in physics sometimes replace a constant with a new invented particle that can substantiate equilibrium or its cousin "equal" I'll look in the vacuum cleaner bag next time I have a chance for any new particles. You know, *a well known former ham Stephen Best got hold of a new antenna program that had strict adherence to Maxwells laws. The program relied on Poynting circle as being representitive * for all forces in radiation. The program ,probably more than I can afford. produced a radiator that was not straight according to the old wives tale that is propagated by hams. It showed something like a tennis ball where multiple wavelengths of radiator were stuffed inside and where balance or equilibrium was obtained. In his study which was around a half wave radiater produced a radiation pattern that was a perfect hemisphere that all on this group stated was impossible to attain. ( actually it was based on a full wave where the ground plane supplied the mirror image) Possibly in our time, that will make it into the newer physics books, that will force the re thinking of radiation. This paper is on the WWW but I leave it to you to show that it must be in error as it is not yet in the books! I think you mean this: http://www.cst.com/Content/Applications/Article/A+Small,+Efficient,+L... I've been trying to understand it for some time. Again, it's not my place to find your errors. *It's your place to prove and demonstrate your allegations. At the same time opponents will bring forwards Toms adage W8TI, that for maximum efficiency a radiator must be straight, thus leaving him with the onus of showing that Steven Best efforts were all wrong by the use of the soon to be corrected theory corrections before old theories are fully discounted where all may read it for themselves in *a book. Dr Best didn't seem to mention anything about the design being any more efficient than a larger antenna. *He had a design requirement to fit an antenna inside a 0.04 wavelength diameter ball, and optimized his design around that requirement. *Getting 1.6dBi of gain out such a small antenna is impressive. Incidentally, his design is NOT a half-hemisphere. *He uses the symmetry of the antenna to dramatically reduce his calculation time. Yes, there are some things that NEC doesn't so very well, or rather other programs do much better. *For example, for microstrip and slot antennas, I'm trying to learn Mstrip40: http://www.spl.ch/software/MultiSTRIP/Manual.htm when not posting inane drive to Usenet. -- Jeff Liebermann * * 150 Felker St #D * *http://www.LearnByDestroying.com Santa Cruz CA 95060http://802.11junk.com Skype: JeffLiebermann * * AE6KS * *831-336-2558 Jeff, Art is going to be your buddy forever. He doesn't care whether you praise him, bash him or anything in between, but he loves long replies. Jimmie |
Causes of Distrust of NEC and Mininec programs
Art Unwin wrote:
So you are a millionare today? Patent number? The present industry is advocating the invention of a new science with respect to obtaining smaller radiators. Get in there and double your money while the consortium continue to struggle with the design of a new technology.alternative than that supplied by nature. If you had such knowledge you would not be persueing insults in place of debate. Just as a non-insulting question, to what do you attribute the principles you describe not being discovered until radio and antenna technology becoming fairly mature? Given that physically small radiators have been desirable just about forever, it is interesting that no one has not accidentally stumbled upon your type of antenna at least once in the past hundred years. One would not have to ascribe to your interesting views on physics to accidentally produce something that works according to your principles. Sweeping an antenna over a wide range should produce clues, if not understanding. Which is to say I'd ordinarily expect things to happen in a particular order typically in one or two modes: 1. Discover the effect accidentally. 2. Reproduce the effect. 3. Come up with good theory to support the effect. Way two 1. Theorize the effect. 2. Build the apparatus to prove it. 3. Reproduce the results. Either way is fine much has been learned through honest sweat as well as cerebral horsepower. - 73 de Mike N3LI - |
Causes of Distrust of NEC and Mininec programs
On Nov 16, 1:03*pm, Michael Coslo wrote:
Art Unwin wrote: So you are a millionare today? *Patent number? The present industry is advocating the invention of a new science with respect to obtaining smaller radiators. Get in there and double your money while the consortium continue to struggle with the design of a new technology.alternative than that supplied by nature. If you had such knowledge you would not be persueing insults in place of debate. Just as a non-insulting question, to what do you attribute the principles you describe not being discovered until radio and antenna technology becoming fairly mature? *Given that physically small radiators *have been desirable just about forever, it is interesting that no one has not accidentally stumbled upon your type of antenna at least once in the past hundred years. One would not have to ascribe to your interesting views on physics to accidentally produce something that works according to your principles. Sweeping an antenna over a wide range should produce clues, if not understanding. Which is to say I'd ordinarily expect things to happen in a particular order typically in one or two modes: 1. Discover the effect accidentally. 2. Reproduce the effect. 3. Come up with good theory to support the effect. Way two 1. Theorize the effect. 2. Build the apparatus to prove it. 3. Reproduce the results. Either way is fine much has been learned through honest sweat as well as cerebral horsepower. * * * * - 73 de Mike N3LI - I think Art is trying to get the members of this group to test or affirm his theories for him so all he has to do is sit on his butt and toss out hair brained ideas. IMO he is desperate for either money or recognition or maybe his life is so boring doing this is all he has left. That would be very sad. I guess if we wanted to be really mean to him we could all just agree with everything he says. Jimmie Jimmie |
Causes of Distrust of NEC and Mininec programs
On Mon, 16 Nov 2009 06:56:16 -0800 (PST), JIMMIE
wrote: Jeff, Art is going to be your buddy forever. He doesn't care whether you praise him, bash him or anything in between, but he loves long replies. Jimmie Sorry, but I don't have the time to craft a short reply. -- Jeff Liebermann 150 Felker St #D http://www.LearnByDestroying.com Santa Cruz CA 95060 http://802.11junk.com Skype: JeffLiebermann AE6KS 831-336-2558 |
Causes of Distrust of NEC and Mininec programs
On Nov 15, 10:42*pm, Art Unwin wrote:
Was it the arabs that expanded the term to equilibrium that could accompany the use of boundary laws? Lurch imitation.. ugggggghhhhhhhhhhhhhhh...... Again, it's not my place to find your errors. *It's your place to prove and demonstrate your allegations. That cannot be done when others rely on theories because they are seen written in a book. It takes corroberation with existing laws to supply a modicom of science teachings *where those agreements can then be built upon. This is a repeat of the battles of faith versus the observations and deductions provided by science. It could be done quite easily. All you have to do is build the antenna, and then compare it with known benchmarks. But of course, that would be using common sense. :/ It would also prove your theories are flawed, which is why you won't do this in public, if at all. At the same time opponents will bring forwards Toms adage W8TI, that for maximum efficiency a radiator must be straight, thus leaving him with the onus of showing that Steven Best efforts were all wrong by the use of the soon to be corrected theory corrections before old theories are fully discounted where all may read it for themselves in *a book. #1, it's W8JI, not W8TI, and what he said was correct. You are just taking what he said out of context and are distorting it to fit your agenda. If you have a straight radiator of a certain length, yes, the most efficient configuration will be a straight line. If you take this same length of wire and mangle it into various bends, twists and turns, loss will rear it's ugly head. Deal with it. There is no free lunch. Dr Best didn't seem to mention anything about the design being any more efficient than a larger antenna. *He had a design requirement to fit an antenna inside a 0.04 wavelength diameter ball, and optimized his design around that requirement. *Getting 1.6dBi of gain out such a small antenna is impressive. Yes, but more important was the ability to stuff wavelengths of radiator showing past erronius suggestion that a radiator must be straight.On top of that he attained a hemisperical radiation pattern that this group stated was impoissible. Thus another false old wives tale was debunked, By the way the paper in no way suggested a "electrically" small antenna, *only a "physically" smaller antenna, so you need to re read the paper. Ugh.. 1.6dbi gain is still less than a straight dipole.. There is no free lunch when you use linear loading. Which BTW, is a technique as old as dirt.. :/ Just because someone decides to call it a fancy name such as "fractal", does not impart magic qualities to this old as dirt technique. BTW, it's quite possible one will need a matching device with such an antenna. Even more loss. :( If you don't require matching for this wonder of technology, I'd suspect you probably have re-invented the dummy load. But maybe that's a moot point, being as you have ignored others that point out the same thing over and over again. IE: all radiators are quite capable of radiating nearly all power that is applied to them. It's getting the power to them without it turning to heat which is the real trick. Good luck in the contest. You are going to need it. Phew, that was a long questionaire but as always my life and thoughts is an open book. I thought you had a problem with books? According to you, books corrupt the mind. Does that mean we would be best off to ignore everything you write? I hope the above satisfies your needs! I doubt it was as good for him as it was for you. You just seem to lay there. :/ |
Causes of Distrust of NEC and Mininec programs
On Mon, 16 Nov 2009 10:25:39 -0800 (PST), JIMMIE
wrote: I think Art is trying to get the members of this group to test or affirm his theories for him so all he has to do is sit on his butt and toss out hair brained ideas. IMO he is desperate for either money or recognition or maybe his life is so boring doing this is all he has left. That would be very sad. I guess if we wanted to be really mean to him we could all just agree with everything he says. When it comes to antenna theory and practice, it would be better to simply acknowledge Stanley Unwin as being more knowledgeable than Art Unwin. |
Causes of Distrust of NEC and Mininec programs
On Sun, 15 Nov 2009 21:20:09 -0600, tom wrote:
And try to learn to spell. Good point. Looks like Art is using Firefox 3.5.5 under OS/X 10.5 and Google Groups. There's no built in spelling chequer in Google Groups but there are plenty of add-on spelling chequers for Firfox. Go thee unto: https://addons.mozilla.org/en-US/firefox and find something that's usable. -- 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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