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#31
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No Cecil it is not about transmission lines it is about a parallel circuit
that radiates. Most of this group are Americans so they all read a book for a formula that might fit what we are talking about. One trots out a simple formula for the Q of a parallel circuit and yells Eureeeeeka and they all follow like Lemmings hooking themselves on this formula that they found in a book. It is a really simple formula but did anybody think for themselves? Ofcourse they didn't, its a simple formula so all that is needed is to parrot it out and follow people who yell loudly that they know what they are talking about. Roy and Shakespeare started it off years ago, yes Wes and many others followed suit and Walter, well he said nothing. Now I ask you Cecil they trot out this formula for Q, it is in books so they feel safe or it would not be in a book right? Now I ask you Cecil if you make an antenna array and you decide that you require an input Z for this array what other values do you need for this very simple formula bearing in mind that is a parallel circuit containing a capacitor of unknown value a inductance of unknown value and then come up with an air of knoweledge. Isn't it crazy ? On top of all that they use a formula that is in a book without determining where it comes from and what it is relevant to and what the simple values represent. Reg saw the problem a long while ago but I think he looked to the sky, shook his head and maybe snickered to himself. I am sure he knows that when you use a formula you can't pick and choose what you insert in a formula. If you are thinking impedance, resistance or whatever and you have a huge physical circuit that contains yards and yards of members that radiate as well as connecting to other passive circuits one would figure that these radiating members would have an impact on this simple circuit that was in a book. And right from the beginning none of them know how long these members are and what diameter and the configuration is even tho they keep spewing their technical garbage because after all they are experts and thus they determine who is right or wrong, whether they be manufacturers, antenna designers or learning amateurs. So tell me Cecil the parallel circuit is in a book and for years I have tried to get people to think for themselves but they can't because this simple formula is in a book so any thinking goes out the window. I find it unbelievable that so many technical people this side of the pond did not even think of looking beyond a book that has this formula in it with only three components and not one thought about inserting figures into it and resolving things for themselves. Yup the idea of figuring out all those resistances was too much for them so they sat back and trotted out phrases from a book that referred to a simple bandpass circuit possibly the size of a finger nail and then sat back and said it was good enough for a 160 meter antenna as we can ignore the wire or radiating members up there as being inconsequential. I ask you Cecil as one who has also also bore the brunt of uneducated attacks what were they taught at school over here that allowed them to bandy this formula around without understanding what it means. No, don't tell me it is beyond anybody to provide a reasonable explanation all they care about is crowding around Madame Guilliotine and cheering as somebody gets killed. Gentlemen if I can call you that go now back to your books and figure out the pertinent figures that is needed for this simple formula and then think about all those nasty things you have said O and by the way remember you can add a shunt resistance if the impedance ratio gets a bit high but then you will have to go back to a book to find out where to put it, I could tell you but I will refrain, a couple of years to figure it out may be beneficial "Cecil Moore" wrote in message ... aunwin wrote: Not sure what you are getting at. Well, how about this, Art? A 1/2WL dipole is similar to a series circuit, i.e. low resistance increasing to each side. A one wavelength dipole is similar to a parallel circuit, i.e. high resistance decreasing to each side. -- 73, Cecil http://www.qsl.net/w5dxp -----= Posted via Newsfeeds.Com, Uncensored Usenet News =----- http://www.newsfeeds.com - The #1 Newsgroup Service in the World! -----== Over 100,000 Newsgroups - 19 Different Servers! =----- |
#32
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On Sun, 07 Mar 2004 02:47:16 GMT, "aunwin"
wrote: Now I ask you Cecil .... Now I ask you Cecil .... So tell me Cecil .... I ask you Cecil .... the world wonders.... Hi Art, Waiting for the fresh mist of the mountain dell to grace your visage? ;-) Perhaps you can tell us what source (no books count) of your definition of Q? I doubt it was at the knee of lord plushbottom (a rather grisly prospect, eh what?). 73's Richard Clark, KB7QHC |
#33
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Art, KB9MZ wrote:
"It is really a simple formula so all that is needed is to parrot it out and follow people who yell loudly that they know what they know what they are talking about. Roy and Shakespeare started it off years ago, yes Wes and many others followed suit and Walter, well he said nothing. Now I ask you Cecil they trot out the formula for Q, it is in books so they feel safe or it would not be in a book right?" All the people Art mentiomned have contributed to this newsgroup and understood how things work. They`ve read the books, benefitted from the knowledge and its application. They are confident in the book knowledge from experience. They are real engineers who know what to use and how and when to use it. That`s different from the handbook experts who often blunder from shallow knowledge and lack of experience. Books are accumulated knowledge that allow us to exploit the experience of others so we don`t have to repeat all the mistakes. As for Q, it is a definition that simplifies formulas. The basis of Q is: the energy stored per cycle versus the energy lost per cycle. You can find that basic definition of Q in any number of books for yourself if you want to look it up. The people Art listed aren`t yelling loudly that: "they hnow what they know!" They are demonstrating their knowledge in their postings which explain andf quantify. Some have their fun too. Despite what Art posted, you can pick and choose what you insert in a formula. "What if" is one of the most rewarding games arounnd. Antenna programs are good examples. Best regards, Richard Harrison, KB5WZI |
#34
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"aunwin" wrote in message news:U2w2c.130951$4o.169497@attbi_s52...
No Cecil it is not about transmission lines it is about a parallel circuit that radiates. Where did he mention transmission lines? I thought he was comparing a 1/2 wave dipole to a full wave dipole as far as circuit description... Most of this group are Americans so they all read a book for a formula that might fit what we are talking about. All? I think not, Art... One trots out a simple formula for the Q of a parallel circuit and yells Eureeeeeka and they all follow like Lemmings hooking themselves on this formula that they found in a book. They did? I guess I missed it... It is a really simple formula but did anybody think for themselves? I can ONLY think for myself. I have failed to master the art of thinking for others... Ofcourse they didn't, its a simple formula so all that is needed is to parrot it out and follow people who yell loudly that they know what they are talking about. I have no idea what you are talking about... Roy and Shakespeare started it off years ago, yes Wes and many others followed suit and Walter, well he said nothing. I thought Shakespeare was an old fart that lived in England. How did he join this illustrious grouping of Americans? Now I ask you Cecil they trot out this formula for Q, it is in books so they feel safe or it would not be in a book right? Right? Now I ask you Cecil if you make an antenna array and you decide that you require an input Z for this array what other values do you need for this very simple formula bearing in mind that is a parallel circuit containing a capacitor of unknown value a inductance of unknown value and then come up with an air of knoweledge. Why are the values unknown? But even discarding that question, what is the big deal about designing a parallel circuit? I've done it many, many times. The formula for Q never even entered my skull. I really don't even need inductance or cap values. Why? Cuz I'm the wizard of burdine street....:/ I work from sense of smell. ![]() a hint as it applies to a base fed 10m 1/2 wave vertical. The usual cap value is appx 50 pf. Didn't need no stinkin formula to come up with that...Dang...I must surely be cracked to work the way I do... Isn't it crazy ? On top of all that they use a formula that is in a book without determining where it comes from and what it is relevant to and what the simple values represent. I'm curiuous...Who was the American that offered this formula for parallel circuits? I must have missed it. Reg saw the problem a long while ago but I think he looked to the sky, shook his head and maybe snickered to himself. I think Reg does that nearly every day. If the wine and "entertainment" is good, he may even snicker out loud... I am sure he knows that when you use a formula you can't pick and choose what you insert in a formula. If you are thinking impedance, resistance or whatever and you have a huge physical circuit that contains yards and yards of members that radiate as well as connecting to other passive circuits one would figure that these radiating members would have an impact on this simple circuit that was in a book. What simple circuit? What book? And right from the beginning none of them know how long these members are and what diameter and the configuration is even tho they keep spewing their technical garbage because after all they are experts and thus they determine who is right or wrong, whether they be manufacturers, antenna designers or learning amateurs. Why do we not know what diameter and the configuration is? Who's fault is this? So tell me Cecil the parallel circuit is in a book and for years I have tried to get people to think for themselves but they can't because this simple formula is in a book so any thinking goes out the window. Can we spell broke record? Art, again, I ONLY think for myself. You couldn't afford my price to think for you, or any others... I don't think for free. Besides, I don't need any extra leads or wiring coming out of my ears, mouth, or my other skull openings... I find it unbelievable that so many technical people this side of the pond did not even think of looking beyond a book that has this formula in it with only three components and not one thought about inserting figures into it and resolving things for themselves. I will find it amazing if anyone can understand what the heck you are harping about...Frankly, all this extended diatribe is confusing to most I think. Double so, if you are an ignorant redneck like me... Yup the idea of figuring out all those resistances was too much for them so they sat back and trotted out phrases from a book that referred to a simple bandpass circuit possibly the size of a finger nail and then sat back and said it was good enough for a 160 meter antenna as we can ignore the wire or radiating members up there as being inconsequential. As previously noted. It's hard to understand what the heck you are talking about. I remember no such thing ocurring...Thread name? I ask you Cecil as one who has also also bore the brunt of uneducated attacks what were they taught at school over here that allowed them to bandy this formula around without understanding what it means. Cecil was attacked? Did he survive? Did the formula survive? No, don't tell me it is beyond anybody to provide a reasonable explanation Ok, I won't... all they care about is crowding around Madame Guilliotine and cheering as somebody gets killed. http://www.stud.hh.se/org/hasp/02/gala/6.html I see them cheering and crowding around her, but I see no body... Gentlemen if I can call you that No, I'm a redneck. Most "gentlemen" shave their legs, and eat quiche energy bars... go now back to your books and figure out the pertinent figures that is needed for this simple formula Why? Will there be a test? and then think about all those nasty things Nasty? Whoa daddy, stand back....He's hurling a nasty... you have said O and by the way remember you can add a shunt resistance if the impedance ratio gets a bit high but then you will have to go back to a book to find out where to put it, He will? What if he doesn't own the book? I could tell you but I will refrain, a couple of years to figure it out may be beneficial Typical....What, is this some big dark secret? I think we should rename this group, rec.radio.peyton.place :/ MK |
#35
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![]() Mark, From the following list, select all that apply. 1. There's a full moon. 2. "Don't know whether he's/I'm washing or hanging out." 3. "He's/I'm as lost as a ball in high weeds." 4. "Shazzam, Sargent Carter!" I've decided that Art is a force of nature, sort of like the tides. One minute it's coming in, the next minute it's going back out. I'm in the process of compiling a "Tide Table" for Art. The period is fairly predictable, it's the variations that are a bit tricky, haven't got a handle on all those, yet. Observations would be appreciated... 'Doc |
#36
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#37
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![]() "aunwin" wrote in message news:aqK1c.176934$jk2.646180@attbi_s53... Why must only series circuits be considered for radiators?. The last discription I saw of a quarter wavw antenna was that of a paralell circuit. Isnt that basically how a capacity hat shortens an antenna, by increasing the paralell capacitance What is it about parallel circuits that make them unsuitable? Who says they are not. Is stagger tuning a parallel circuit ? This question being out of context with the other questions seems to indicate you really dont know what stagger tuning means so I dont know how to reply. Regards Art |
#38
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![]() "Richard Harrison" wrote in message ... A parallel resonsant circuit is a high impedance (low admittance). est regards, Richard Harrison, KB5WZI Now go back to your books since your memory is poor and check out what restrictions apply. Do you ignore all connection lengths between lumped circuits. Do they say all parallel circuits ALWAYS have a high impedance without exception? Does this simple formula account for radiation ? Does a parallel circuit in macro form that radiates apply with respect to this simple formula regardless of interconnection lengths? Must all distributed passive forms be ignored and why? |
#39
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![]() "Richard Harrison" wrote in message ... onant as a model may be based on application or impedance. A parallel resonant circuit exhibits high impedance. Read what the book says about circuits that exhibit high impedance and what the formula omits as being inconsequential With reference to a large radiating parallel circuit containing both distributed and lumped passive circuits figure out what the numbers are that you can or can not place in the simple circuit that proves your point. I regret Art fails to see the relevance of much of the accurate information offered. Best regards, Richard Harrison, KB5WZI |
#40
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Jimmy wrote:
"The last description I saw of a quarter wave antenna was that of a parallel circuit. Isn`t that basically how a capacity hat shortens an antenna, by increasing the parallel capacitance?" Parallel or series hardly makes any difference. The 1/4-wave antenna is essentially a 1/2-wave antenna with the missing 1/4-wave piece replaced by a ground reflection. Terman illustrates current distribution in a doublet on page 866 of his 1955 edition. He says: "These current distributions are those that would be obtained by applying the exciting voltage in series with the wire at a current loop, or to one end of the wire." The series representation is conventional and comes from the distributed nature of resistance, inductance, and capacitance along the antenna wire. From the generator or transmission line`s point of view, it may be more convenient to view the antenna load as a parallel resonant circuit. Parallel or series circuit, they are mathematically interchangeable by using conversion formulas which appear in various books including the ARRL Antenna Book. Use whichever form you like. There is a difference between a length of wire and a tank circuit. The wire has multiple harmonically related resonances. The tank circuit does not. It has only one resonance. Jimmy also wrote: "Who says they are not (parallel circuits suitable to model an antenna)?" Yes, Art Unwin, who says they are not? Jimmy also wrote: "This question (is stagger tuning a parallel circuit?) being out of context with the other questions seems to indicate you really don`t know what stagger tuning means so I don`t know how to reply." Art for years has hijacked threads to advertise a tuned loop conjoined with a dipole. One of his claims is that the loop is tuned to one frequency and the dipole is tuned to a different frequency ergo a broadband antenna is produced. You must guess between the lines to make sense of what Art says. Best regards, Richard Harrison, KB5WZI |
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