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antenna physics question
On Dec 14, 8:53*pm, wrote:
K1TTT wrote: On Dec 14, 8:10*pm, wrote: K1TTT wrote: On Dec 14, 4:54*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. Non-dimensional metadata doesn't always provide the complete context. Dimensional metadata provides greater context because it conveys more detailed and specific information. Only an ignorant, anal retentive git would think that basic terminology has to be defined each and every time it is used. "Antenna efficiency is 20%" has all the information required and if the discussion is about antennas, "efficiency is 20%" has all the information required. When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. really? *i don't see either 'efficiency' or 'antenna efficiency' in either my 2nd edition of jackson's classical electrodynamics, or ramo,whinnery, and van duzer's fields and waves in communication electronics... if you know where those terms might be defined in either of those please let me know, maybe the indexes aren't complete or something. First book I pick up, Electromagnetics by Kraus and Carver. So change "any textbook" to "many textbooks". -- Jim Pennino Remove .spam.sux to reply. but your basic point still fails... the definition of efficiency is not universal, unique, nor unambiguous since it is not in ALL textbooks, nor is it a simple single definition, as my list of qualifiers in the ieee handbook illustrates.... oh, and those many definitions are not just restating the same thing, they are VERY different definitions depending on the aspect of the antenna you are studying. The fact that it is not in all textbooks is irrelvant. Not everything is in all textbooks of any kind. There are many scientific and engineering terms that can have qualifiers to denote specificity. And in most every case there is a qualified term that is in most common use and is commonly used without the qualifier. Every engineer I know when discusssing antennas in general that say "antenna efficieny" mean "antenna radiation efficiency". The ARRL Antenna Handbook, when talking about "antenna efficieny", refers to "antenna radiation efficiency". For most of the links of the 7,000,000 or so when you search for "antenna efficieny" you come to a link that refers to "antenna radiation efficiency". -- Jim Pennino Remove .spam.sux to reply. ah, so you have performed a contextual statistical analysis on 7M links in the last half hour... thats pretty good processing. what you got for a computer there? |
antenna physics question
K1TTT wrote:
On Dec 14, 8:53Â*pm, wrote: K1TTT wrote: On Dec 14, 8:10Â*pm, wrote: K1TTT wrote: On Dec 14, 4:54Â*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. Non-dimensional metadata doesn't always provide the complete context. Dimensional metadata provides greater context because it conveys more detailed and specific information. Only an ignorant, anal retentive git would think that basic terminology has to be defined each and every time it is used. "Antenna efficiency is 20%" has all the information required and if the discussion is about antennas, "efficiency is 20%" has all the information required. When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. really? Â*i don't see either 'efficiency' or 'antenna efficiency' in either my 2nd edition of jackson's classical electrodynamics, or ramo,whinnery, and van duzer's fields and waves in communication electronics... if you know where those terms might be defined in either of those please let me know, maybe the indexes aren't complete or something. First book I pick up, Electromagnetics by Kraus and Carver. So change "any textbook" to "many textbooks". -- Jim Pennino Remove .spam.sux to reply. but your basic point still fails... the definition of efficiency is not universal, unique, nor unambiguous since it is not in ALL textbooks, nor is it a simple single definition, as my list of qualifiers in the ieee handbook illustrates.... oh, and those many definitions are not just restating the same thing, they are VERY different definitions depending on the aspect of the antenna you are studying. The fact that it is not in all textbooks is irrelvant. Not everything is in all textbooks of any kind. There are many scientific and engineering terms that can have qualifiers to denote specificity. And in most every case there is a qualified term that is in most common use and is commonly used without the qualifier. Every engineer I know when discusssing antennas in general that say "antenna efficieny" mean "antenna radiation efficiency". The ARRL Antenna Handbook, when talking about "antenna efficieny", refers to "antenna radiation efficiency". For most of the links of the 7,000,000 or so when you search for "antenna efficieny" you come to a link that refers to "antenna radiation efficiency". -- Jim Pennino Remove .spam.sux to reply. ah, so you have performed a contextual statistical analysis on 7M links in the last half hour... thats pretty good processing. what you got for a computer there? No, I looked at the first four and all of them were referring to "antenna radiation efficiency". Then I scanned the summaries that Google gives for the first page of hits and found that all but one referred to "antenna radiation efficiency". The one exception was on a page about satellite calculations and they were referring to "antenna aperature efficieny", as would be expected from the context. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 14, 9:25*pm, wrote:
K1TTT wrote: On Dec 14, 8:53*pm, wrote: K1TTT wrote: On Dec 14, 8:10*pm, wrote: K1TTT wrote: On Dec 14, 4:54*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. Non-dimensional metadata doesn't always provide the complete context. Dimensional metadata provides greater context because it conveys more detailed and specific information. Only an ignorant, anal retentive git would think that basic terminology has to be defined each and every time it is used. "Antenna efficiency is 20%" has all the information required and if the discussion is about antennas, "efficiency is 20%" has all the information required. When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. really? *i don't see either 'efficiency' or 'antenna efficiency' in either my 2nd edition of jackson's classical electrodynamics, or ramo,whinnery, and van duzer's fields and waves in communication electronics... if you know where those terms might be defined in either of those please let me know, maybe the indexes aren't complete or something. First book I pick up, Electromagnetics by Kraus and Carver. So change "any textbook" to "many textbooks". -- Jim Pennino Remove .spam.sux to reply. but your basic point still fails... the definition of efficiency is not universal, unique, nor unambiguous since it is not in ALL textbooks, nor is it a simple single definition, as my list of qualifiers in the ieee handbook illustrates.... oh, and those many definitions are not just restating the same thing, they are VERY different definitions depending on the aspect of the antenna you are studying. The fact that it is not in all textbooks is irrelvant. Not everything is in all textbooks of any kind. There are many scientific and engineering terms that can have qualifiers to denote specificity. And in most every case there is a qualified term that is in most common use and is commonly used without the qualifier. Every engineer I know when discusssing antennas in general that say "antenna efficieny" mean "antenna radiation efficiency". The ARRL Antenna Handbook, when talking about "antenna efficieny", refers to "antenna radiation efficiency". For most of the links of the 7,000,000 or so when you search for "antenna efficieny" you come to a link that refers to "antenna radiation efficiency". -- Jim Pennino Remove .spam.sux to reply. ah, so you have performed a contextual statistical analysis on 7M links in the last half hour... thats pretty good processing. *what you got for a computer there? No, I looked at the first four and all of them were referring to "antenna radiation efficiency". Then I scanned the summaries that Google gives for the first page of hits and found that all but one referred to "antenna radiation efficiency". The one exception was on a page about satellite calculations and they were referring to "antenna aperature efficieny", as would be expected from the context. -- Jim Pennino Remove .spam.sux to reply. oh, so from skimming a dozen links and only finding one who's apparent reference wasn't what you were looking for that makes 'most' of the other 7M fit your definition also. i know that polling works for politicians to declare that they are going to win by only asking a few hundred out of millions, but at least they don't just ask the first few people they meet on the street and assume that they represent the rest of the country. |
antenna physics question
K1TTT wrote:
On Dec 14, 9:25Â*pm, wrote: K1TTT wrote: On Dec 14, 8:53Â*pm, wrote: K1TTT wrote: On Dec 14, 8:10Â*pm, wrote: K1TTT wrote: On Dec 14, 4:54Â*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. Non-dimensional metadata doesn't always provide the complete context. Dimensional metadata provides greater context because it conveys more detailed and specific information. Only an ignorant, anal retentive git would think that basic terminology has to be defined each and every time it is used. "Antenna efficiency is 20%" has all the information required and if the discussion is about antennas, "efficiency is 20%" has all the information required. When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. really? Â*i don't see either 'efficiency' or 'antenna efficiency' in either my 2nd edition of jackson's classical electrodynamics, or ramo,whinnery, and van duzer's fields and waves in communication electronics... if you know where those terms might be defined in either of those please let me know, maybe the indexes aren't complete or something. First book I pick up, Electromagnetics by Kraus and Carver. So change "any textbook" to "many textbooks". -- Jim Pennino Remove .spam.sux to reply. but your basic point still fails... the definition of efficiency is not universal, unique, nor unambiguous since it is not in ALL textbooks, nor is it a simple single definition, as my list of qualifiers in the ieee handbook illustrates.... oh, and those many definitions are not just restating the same thing, they are VERY different definitions depending on the aspect of the antenna you are studying. The fact that it is not in all textbooks is irrelvant. Not everything is in all textbooks of any kind. There are many scientific and engineering terms that can have qualifiers to denote specificity. And in most every case there is a qualified term that is in most common use and is commonly used without the qualifier. Every engineer I know when discusssing antennas in general that say "antenna efficieny" mean "antenna radiation efficiency". The ARRL Antenna Handbook, when talking about "antenna efficieny", refers to "antenna radiation efficiency". For most of the links of the 7,000,000 or so when you search for "antenna efficieny" you come to a link that refers to "antenna radiation efficiency". -- Jim Pennino Remove .spam.sux to reply. ah, so you have performed a contextual statistical analysis on 7M links in the last half hour... thats pretty good processing. Â*what you got for a computer there? No, I looked at the first four and all of them were referring to "antenna radiation efficiency". Then I scanned the summaries that Google gives for the first page of hits and found that all but one referred to "antenna radiation efficiency". The one exception was on a page about satellite calculations and they were referring to "antenna aperature efficieny", as would be expected from the context. -- Jim Pennino Remove .spam.sux to reply. oh, so from skimming a dozen links and only finding one who's apparent reference wasn't what you were looking for that makes 'most' of the other 7M fit your definition also. It is called statistical sampling and is most appropriate for Google as the links returned are ordered by relevance. I do note you have nothing to say about the other two statements; what, no nits to pick there? -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 14, 10:36*pm, wrote:
K1TTT wrote: On Dec 14, 9:25*pm, wrote: K1TTT wrote: On Dec 14, 8:53*pm, wrote: K1TTT wrote: On Dec 14, 8:10*pm, wrote: K1TTT wrote: On Dec 14, 4:54*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. |
antenna physics question
K1TTT wrote:
On Dec 14, 10:36Â*pm, wrote: K1TTT wrote: On Dec 14, 9:25Â*pm, wrote: K1TTT wrote: On Dec 14, 8:53Â*pm, wrote: K1TTT wrote: On Dec 14, 8:10Â*pm, wrote: K1TTT wrote: On Dec 14, 4:54Â*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. Non-dimensional metadata doesn't always provide the complete context. Dimensional metadata provides greater context because it conveys more detailed and specific information. Only an ignorant, anal retentive git would think that basic terminology has to be defined each and every time it is used. "Antenna efficiency is 20%" has all the information required and if the discussion is about antennas, "efficiency is 20%" has all the information required. When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. really? Â*i don't see either 'efficiency' or 'antenna efficiency' in either my 2nd edition of jackson's classical electrodynamics, or ramo,whinnery, and van duzer's fields and waves in communication electronics... if you know where those terms might be defined in either of those please let me know, maybe the indexes aren't complete or something. First book I pick up, Electromagnetics by Kraus and Carver. So change "any textbook" to "many textbooks". -- Jim Pennino Remove .spam.sux to reply. but your basic point still fails... the definition of efficiency is not universal, unique, nor unambiguous since it is not in ALL textbooks, nor is it a simple single definition, as my list of qualifiers in the ieee handbook illustrates.... oh, and those many definitions are not just restating the same thing, they are VERY different definitions depending on the aspect of the antenna you are studying. The fact that it is not in all textbooks is irrelvant. Not everything is in all textbooks of any kind. There are many scientific and engineering terms that can have qualifiers to denote specificity. And in most every case there is a qualified term that is in most common use and is commonly used without the qualifier. Every engineer I know when discusssing antennas in general that say "antenna efficieny" mean "antenna radiation efficiency". The ARRL Antenna Handbook, when talking about "antenna efficieny", refers to "antenna radiation efficiency". For most of the links of the 7,000,000 or so when you search for "antenna efficieny" you come to a link that refers to "antenna radiation efficiency". -- Jim Pennino Remove .spam.sux to reply. ah, so you have performed a contextual statistical analysis on 7M links in the last half hour... thats pretty good processing. Â*what you got for a computer there? No, I looked at the first four and all of them were referring to "antenna radiation efficiency". Then I scanned the summaries that Google gives for the first page of hits and found that all but one referred to "antenna radiation efficiency". The one exception was on a page about satellite calculations and they were referring to "antenna aperature efficieny", as would be expected from the context. -- Jim Pennino Remove .spam.sux to reply. oh, so from skimming a dozen links and only finding one who's apparent reference wasn't what you were looking for that makes 'most' of the other 7M fit your definition also. It is called statistical sampling and is most appropriate for Google as the links returned are ordered by relevance. I do note you have nothing to say about the other two statements; what, no nits to pick there? -- Jim Pennino Remove .spam.sux to reply. no, i'm having enough fun with this nit. Well nit this, as I said Google links are ordered by relevance and starting on the second page you begin to find links to information about the efficiency of a specific antenna as opposed to efficiency in general. If you limit the results to about 57,000 results by putting antenna efficiency in quotes, it is pretty much all specific to an antenna by the third page. Yet the first page doesn't change. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 14, 11:29*pm, wrote:
K1TTT wrote: On Dec 14, 10:36*pm, wrote: K1TTT wrote: On Dec 14, 9:25*pm, wrote: K1TTT wrote: On Dec 14, 8:53*pm, wrote: K1TTT wrote: On Dec 14, 8:10*pm, wrote: K1TTT wrote: On Dec 14, 4:54*pm, wrote: Registered User wrote: On Mon, 13 Dec 2010 19:51:07 -0000, wrote: Have you the slightest clue what the word "context" means? Absolutely, yes I do. In turn I will ask do you know what metadata is? Yes, and I also know what ice cream is, both of which are irrelevant to the discussion. Both dimensional and non-dimensional metadata provide context. Non-dimensional metadata doesn't always provide the complete context. Dimensional metadata provides greater context because it conveys more detailed and specific information. Only an ignorant, anal retentive git would think that basic terminology has to be defined each and every time it is used. "Antenna efficiency is 20%" has all the information required and if the discussion is about antennas, "efficiency is 20%" has all the information required. When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. really? *i don't see either 'efficiency' or 'antenna efficiency' in either my 2nd edition of jackson's classical electrodynamics, or ramo,whinnery, and van duzer's fields and waves in communication electronics... if you know where those terms might be defined in either of those please let me know, maybe the indexes aren't complete or something. First book I pick up, Electromagnetics by Kraus and Carver. So change "any textbook" to "many textbooks". -- Jim Pennino Remove .spam.sux to reply. but your basic point still fails... the definition of efficiency is not universal, unique, nor unambiguous since it is not in ALL textbooks, nor is it a simple single definition, as my list of qualifiers in the ieee handbook illustrates.... oh, and those many definitions are not just restating the same thing, they are VERY different definitions depending on the aspect of the antenna you are studying. The fact that it is not in all textbooks is irrelvant. Not everything is in all textbooks of any kind. There are many scientific and engineering terms that can have qualifiers to denote specificity. And in most every case there is a qualified term that is in most common use and is commonly used without the qualifier. Every engineer I know when discusssing antennas in general that say "antenna efficieny" mean "antenna radiation efficiency". The ARRL Antenna Handbook, when talking about "antenna efficieny", refers to "antenna radiation efficiency". For most of the links of the 7,000,000 or so when you search for "antenna efficieny" you come to a link that refers to "antenna radiation efficiency". -- Jim Pennino Remove .spam.sux to reply. ah, so you have performed a contextual statistical analysis on 7M links in the last half hour... thats pretty good processing. *what you got for a computer there? No, I looked at the first four and all of them were referring to "antenna radiation efficiency". Then I scanned the summaries that Google gives for the first page of hits and found that all but one referred to "antenna radiation efficiency". The one exception was on a page about satellite calculations and they were referring to "antenna aperature efficieny", as would be expected from the context. -- Jim Pennino Remove .spam.sux to reply. oh, so from skimming a dozen links and only finding one who's apparent reference wasn't what you were looking for that makes 'most' of the other 7M fit your definition also. It is called statistical sampling and is most appropriate for Google as the links returned are ordered by relevance. I do note you have nothing to say about the other two statements; what, no nits to pick there? -- Jim Pennino Remove .spam.sux to reply. no, i'm having enough fun with this nit. Well nit this, as I said Google links are ordered by relevance and starting on the second page you begin to find links to information about the efficiency of a specific antenna as opposed to efficiency in general. If you limit the results to about 57,000 results by putting antenna efficiency in quotes, it is pretty much all specific to an antenna by the third page.. Yet the first page doesn't change. -- Jim Pennino Remove .spam.sux to reply. great, now why don't you try some negative searches for the other specific terms that i quoted from the ieee book and see how many links show up for them, then compare the relative numbers of links and their order with the original search... that should keep you busy for a while. |
antenna physics question
On Dec 14, 12:24*pm, Registered User wrote:
On Tue, 14 Dec 2010 05:37:25 -0800 (PST), wrote: On Dec 14, 5:02 am, Registered User wrote: When data gets shared among multiple parties it is important that a ubiquitous language is used to describe the data and its meaning. Antenna efficiency can be measured in different ways so the phrase "antenna efficiency is 20%" can mean different things to different people. All it takes is one person to ask how antenna efficiency is calculated and it will become evident that context of "antenna efficiency is 20%" does not provide all the information required. Sure it does. *Antenna efficiency is only calculated one way, so there is no need to add extra "metadata". Funny thing, when working parabolic antennas antenna efficiency and aperture efficiency are used interchangeably. I find that a funny thing, since they define two different things. They are not the same thing, and should not be confused, intermingled, or even paired up on the same date to go watch Star Wars at the midnight movies. If I were to refer to aperture efficiency, I would call it aperture efficiency, effective aperture, or maybe even antenna effective area, but not antenna efficiency. |
antenna physics question
K1TTT wrote:
great, now why don't you try some negative searches for the other specific terms that i quoted from the ieee book and see how many links show up for them, then compare the relative numbers of links and their order with the original search... that should keep you busy for a while. It took about 10 seconds to cut and paste. 11,000 results with 7 out of 10 of the top results identical. It appears your efficiency in attempting to deride what I've said is deficient. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 10, 8:37*am, joe wrote:
Art Unwin wrote: *I am sure you also know that only units used by Mawell represent the path to maximum efficiency in radiation as well as the ratio of capacitance to inductance must be *unity. Art KB9MZ....xg Art, You have just mentioned a constraint on antennas that I was not aware of. *Specifically "the ratio of capacitance to inductance must be unity". This is new to me. Please tell me how I go about making capacitance and inductance equal so their ratio can be unity. How do you get the Farads and Henries to cancel out, leaving a dimensionless number. Can you give me some real world examples? joe Joe, a better insight to my thinking that may help When a member has little or no reactance via cancellation you can use V=I.R. When R becomes exceedingly small the member reaches a critical point and will oscillate When this happens current increases dramatically which therefore increases radiation. If you view the current curve on a dipole the current is of cyclic form whereas in the case where critical resistance is reached the current flow is of a very high value pulse which also drops fairly rapidly until it reaches a low point before it gets to the end of a period. When the element oscillates it has become a mechanical movement BELOW the current path and as can be seen by comparing to water flow the raggednes in terms of cross sectional area of flow has createrd eddy currents which in electrical terms is equal to displacement current as it is the creation of displacement current.or coefficient of discharge This states why magnetics as used in non equilibrium structures such as the Yagi cannot be as efficient as a Meander form which achieves higher current which propels or provides for radiation.. What propelled the notion of waves instead of particles is 1 they ignored Gaussian thrust towards equilibrium and 2 turned to the increase in current because of the mechanical "wave" action which only provides change in amplitude which is not enough to provide an acceleration of charge on a particle resting on water since that requires two vectors.( I say a resting particle where as it was never clear what the "wave" was lifting or where it came from. This because the force required to remove an electron from its element habitat required more force than that was available. ( Gravity is termed as the weaker force in the Std model) The bottom line being, a radiating structure in equilibrium devoid of reactance with low resistance is the only way current over and above that supplied becomes available. By the way the std yagi is not a closed circuit as equilibrium requires because the half wave length floats, where as a full wave or "period" is consistent or in a steady state when "overshoot" occurs. Thus only when it is resonant is it devoid of reactance which limits the bandwidth. In the case of a Meander form the magnetic field is not present in cyclic form allowing for surface current flow for extended periods and is not frequency dependant. As I have stated before, with my antenna current distribution is via a surge with rapid decay which is accepted in RC L circuitry. Hope that clears things up for you Regards Art |
antenna physics question
On Dec 15, 3:47*am, Art Unwin wrote:
On Dec 10, 8:37*am, joe wrote: Art Unwin wrote: *I am sure you also know that only units used by Mawell represent the path to maximum efficiency in radiation as well as the ratio of capacitance to inductance must be *unity. Art KB9MZ....xg Art, You have just mentioned a constraint on antennas that I was not aware of. *Specifically "the ratio of capacitance to inductance must be unity". This is new to me. Please tell me how I go about making capacitance and inductance equal so their ratio can be unity. How do you get the Farads and Henries to cancel out, leaving a dimensionless number. Can you give me some real world examples? joe Joe, *a better insight to my thinking that may help When a member has little or no reactance via cancellation you can use V=I.R. When R becomes exceedingly small the member reaches a critical point and will oscillate When this happens current increases dramatically which therefore increases radiation. If you view the current curve on a dipole the current is of cyclic form whereas in the case where critical resistance is reached the current flow is of a very high value pulse which also drops fairly rapidly until it reaches a low point before it gets to the end of a period. When the element oscillates it has become a mechanical movement BELOW the current path and as can be seen by comparing to water flow the raggednes in terms of cross sectional area of flow has createrd eddy currents which in electrical terms is equal to displacement current as it is the creation of displacement current.or coefficient of discharge This states why magnetics as used *in non equilibrium structures such as the Yagi cannot be as efficient as a Meander form which achieves higher current which propels *or provides for radiation.. What propelled the notion of waves instead of particles is 1 they ignored Gaussian thrust towards equilibrium and 2 turned to the increase in current because of the mechanical "wave" action which only provides change in amplitude which is not enough to provide an acceleration of charge on a *particle resting on water since that requires two vectors.( I say a resting particle where as it was never clear what the "wave" was lifting or where it came from. This because the force required to remove an electron from its element habitat required more force than that was available. ( Gravity is termed as the weaker force in the Std model) The bottom line being, a radiating structure in equilibrium devoid of reactance with low resistance is the only way current over and above that supplied becomes available. By the way the std yagi is not a closed circuit as equilibrium requires because the half wave length floats, where as a full wave or "period" is consistent or in a steady state when "overshoot" occurs. Thus only when it is resonant is it devoid of reactance which limits the bandwidth. In the case of a Meander form the magnetic field is not present in cyclic form allowing for surface current flow for extended periods and is not frequency dependant. As I have stated before, with my antenna current distribution is via a surge with rapid decay which is accepted in RC L circuitry. Hope that clears things up for you Regards Art yup, clear as mud with waves. |
antenna physics question
The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993)
provides no definition for 'antenna efficiency' per se. A definition is provided for 'antenna efficiency of an aperture-type antenna' in section 2.15 of the document. The definitions are in alphabetical order so the definition describing the ratio of power radiated to input power appears in section 2.308 which is titled 'radiation efficiency' (notice the dimensional metadata). These citations from IEEE Standard Definitions Terms for Antennas clearly suggest claims of a universal formula and definition for antenna efficiency are incorrect. Not everyone means the same although they use the same name. This is why it is important to define or refer to the definitions that are used. |
antenna physics question
Registered User wrote:
The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? The term is in common use and can by found in many textbooks on electromagnetics in general and antennas in particular, several books by the ARRL as well as on many technical web pages. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 15, 3:29*pm, wrote:
Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? The term is in common use and can by found in many textbooks on electromagnetics in general and antennas in particular, several books by the ARRL as well as on many technical web pages. -- Jim Pennino Remove .spam.sux to reply. so what? |
antenna physics question
K1TTT wrote:
On Dec 15, 3:29Â*pm, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? The term is in common use and can by found in many textbooks on electromagnetics in general and antennas in particular, several books by the ARRL as well as on many technical web pages. -- Jim Pennino Remove .spam.sux to reply. so what? So the fact that a particular IEEE standard does not mention a term that is in common use is irrelevant to the fact that the term is in common use. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
Registered User wrote:
On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. snip remaining long winded babble -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 15, 8:49*pm, wrote:
Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. some of us help write and test those standards. and it sure would be nice if we could refer to a standard way of describing antenna performance. |
antenna physics question
On Dec 15, 8:49*pm, wrote:
Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. some of us help write and test those standards. and it sure would be nice if we could refer to a standard way of describing antenna performance. |
antenna physics question
K1TTT wrote:
On Dec 15, 8:49Â*pm, wrote: Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. some of us help write and test those standards. and it sure would be nice if we could refer to a standard way of describing antenna performance. If this is so important to you, I am sure you will be researching all the electromagnetics textbooks, antenna texbooks, industry and trade publications, the ARRL, the RSGB, manufacturers, and everyone else with any interest in antennas to determine the "correct" usage and definition of the terms in question, and submitting a draft proposal to the IEEE. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
K1TTT wrote:
On Dec 15, 8:49Â*pm, wrote: Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. some of us help write and test those standards. and it sure would be nice if we could refer to a standard way of describing antenna performance. If I were you I would be more concerned why so many of you posts appear twice. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Dec 15, 11:12*pm, wrote:
K1TTT wrote: On Dec 15, 8:49*pm, wrote: Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. *some of us help write and test those standards. *and it sure would be nice if we could refer to a standard way of describing antenna performance. If this is so important to you, I am sure you will be researching all the electromagnetics textbooks, antenna texbooks, industry and trade publications, the ARRL, the RSGB, manufacturers, and everyone else with any interest in antennas to determine the "correct" usage and definition of the terms in question, and submitting a draft proposal to the IEEE. -- Jim Pennino Remove .spam.sux to reply. nope, i don't care that much, but you sure seem to be insisting there is a correct usage when obviously it hasn't ever been really agreed upon by the right people. so you are the one who should be trying to get all the worlds authors to agree to define it the same way and get it into all the text books where its been missing all these years. |
antenna physics question
K1TTT wrote:
On Dec 15, 11:12Â*pm, wrote: K1TTT wrote: On Dec 15, 8:49Â*pm, wrote: Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. Â*some of us help write and test those standards. Â*and it sure would be nice if we could refer to a standard way of describing antenna performance. If this is so important to you, I am sure you will be researching all the electromagnetics textbooks, antenna texbooks, industry and trade publications, the ARRL, the RSGB, manufacturers, and everyone else with any interest in antennas to determine the "correct" usage and definition of the terms in question, and submitting a draft proposal to the IEEE. -- Jim Pennino Remove .spam.sux to reply. nope, i don't care that much, but you sure seem to be insisting there is a correct usage when obviously it hasn't ever been really agreed upon by the right people. so you are the one who should be trying to get all the worlds authors to agree to define it the same way and get it into all the text books where its been missing all these years. So if the IEEE doesn't mention it in some standard everyone else is wrong? Since there are electromagnetics textbooks, antenna texbooks, ARRL books and web sites that all say the same thing, it appears there is some agreement out there in the real world. As for what's missing in some selection of books, I'm quite sure that if you do a comparison of every book on a given subject there will be differences in the topics covered. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On Wed, 15 Dec 2010 20:49:39 -0000, wrote:
Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble That would be babble about why making blanket statements without adequate research is not an effective decision. That is what you did isn't it? Does everything that questions your highly self-valued input become babble? On Tue, 14 Dec 2010 16:54:40 -0000, wrote: The term "antenna efficiency" has a unique and unambigous definition and can be found in any textbook on electromagnetics. Speaking of babble, which parts of that statement have been shown to be true? The balance can truly be considered babble. The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And let us not overlook how the "a unique and unambigous definition" became "the term is in common use". Adding conditionals to what was a statement of absolute certainty does not make the original assertion any less flawed. That's just woulda, coulda, shoulda revisionism, an attempt to change the question to make it better fit the known answer. What makes that path better than the simple admission of having made a mistake? And nowhere did I reference any standard, IEEE, ISO, or any other standards body. Yep you made no reference to any standards except for the ones you made up. Now you're making excuses for failing to refer to any other standards before making assertions which turned out to be wrong.. Alibi all you wish but the flaws in your assertion of "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" have been exposed. snip remaining long winded babble What you call long-winded babble was - quote - You took what may be a perfectly valid general rule, tried to convert it to an absolute certainty, and failed. That's so what. - end quote - How could those two sentences be made to contain less babble and be made more concise? Denigrate the messenger all you wish but that will not change the fact your blanket statement was nothing more than an uneducated, unfounded opinion. Please note I refer to the opinion as being uneducated and unfounded not the individual. Whatever your education, skills and experience are, the aggregate is unrelated to the fact you come across in the context of a small person who is rather full of himself. Let me just pat you on the head and say 'you win, you're right because you say so'. |
antenna physics question
Registered User wrote:
snip rambling rehashes, nothing left If it is in Electromagnetics by Kraus and Carver, that's good enough for me as an engineer. If it is in the ARRL Antenna Handbook, that's good enough for me as a ham. -- Jim Pennino Remove .spam.sux to reply. |
antenna physics question
On 12/14/2010 9:47 PM, Art Unwin wrote:
Art, You have just mentioned a constraint on antennas that I was not aware of. Specifically "the ratio of capacitance to inductance must be unity". This is new to me. Please tell me how I go about making capacitance and inductance equal so their ratio can be unity. How do you get the Farads and Henries to cancel out, leaving a dimensionless number. Can you give me some real world examples? joe Joe, Snip large meaningless verbiage Regards Art More concisely stated "No". tom K0TAR |
antenna physics question
On Dec 15, 11:13*pm, wrote:
K1TTT wrote: On Dec 15, 8:49*pm, wrote: Registered User wrote: On Wed, 15 Dec 2010 15:29:12 -0000, wrote: Registered User wrote: The IEEE Standard Definitions Terms for Antennas (IEEE Std 145-1993) provides no definition for 'antenna efficiency' per se. So what? snip babble The post concerning "a unique and unambigous definition" which "can be found in any textbook on electromagnetics" and subsequent back-pedaling appears to fit that model. Your "So what?" provides the meh. Yeah, the "back-pedaling" which consisted of changing "any textbook" to "many textbooks". And nowhere did I reference any standard, IEEE, ISO, or any other standards body. well, maybe you should have... after all, some of us do use things written by those bodies. *some of us help write and test those standards. *and it sure would be nice if we could refer to a standard way of describing antenna performance. If I were you I would be more concerned why so many of you posts appear twice. -- Jim Pennino Remove .spam.sux to reply. i think i have figured that out... if i post to the group it takes me right back to reading messages... and then if i do a refresh it must try to do the same post it just did since that is how it got to the current page. i'll try to remember to go back to the message list first which seems to avoid that problem. |
antenna physics question
On Nov 28, 9:32*pm, Art Unwin wrote:
I have been struggling with this for some time so maybe somebody can set me straight. We wind a flat plate spiral antenna and we get to a point where the center medium becomes saturated with flux. Now I add even more coils. What action does that precipitate? I would like to think that the Meissner effect *( perfect diamagnetism) then takes over and swamps the external magnetic field as with a superconductor ( ie opposite to that of a paramagnetic) The skin effect is thus removed allowing the current flow to the surface by allowing the atomic structure to relax, and add to the current already in place to allow fully efficient radiation as it now lies outside the confines of conductor resistance. This is my effort in determining what is it that drives the constant impedance attributes of a meander type array? Regards Art oh, and the answer is R. |
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