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#71
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Anyone know where I can find plans for an artificial ground?
"Szczepan Bialek" wrote in message ... "Wayne" napisal w wiadomosci ... "Szczepan Bialek" wrote in message .. . So with direct coax connection, one leg radiates and the other leg is ground? # Yes. Would you be willing to touch the end of the "ground"/"radial" wire while transmitting? # The electron density changes periodically in the both legs (while # transmitting). # Are the voltages equal in the both legs? But the question was: if the half of the antenna connected to the coax is ground, would you be willing to touch the end of that half while RF power is supplied to the center conductor connected half of the antenna? That would be a good way of verifying your theory. # It is not my theory. Somebody wrote: # "H. Horizontal, unbalanced antennas, such as a long wire or random wire, # need an RF Ground wire that should be 10-15% longer than the antenna wire # itself. This is often called a counterpoise. The RF ground wire in this case # can be laid out in many ways, just so long as it does not cross over itself # to form a loop. Indoors, such wires are often run under carpets or along # walls, out of windows, or anywhere else convenient. This wire will often # have large RF voltages on it, so it should be kept away from people or # insulated to prevent contact." From: # http://www.sgcworld.com/radialstechnote.html # Your "dipoles" are "horizontal, unbalanced antennas". The radial or # counterpoise "should be kept away from people or insulated to prevent # contact." It appears that your reference above from SGC contradicts your single radial assertion. For a half wave antenna broken in the center, you claim that the half connected to the coax braid is a radial. If it is a radial, why does it have high voltage at the end, behaving like a dipole? |
#72
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I wonder if I have gone nuts going through this thread!
73, Nandu. |
#73
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Anyone know where I can find plans for an artificial ground?
"tom" napisal w wiadomosci . .. On 5/1/2013 3:47 AM, Szczepan Bialek wrote: You simply do not know that: "In electronic circuit theory, a "ground" is usually idealized as an infinite source or sink for charge, which can absorb an unlimited amount of current without changing its potential." and, But the "ground" you are referring to in this paragraph is NOT the one you are in the next. One is an essentially infinite sink, and the other ignores that property entirely. So you are arguing with yourself here. The both paragraph are wrote by the same Author. "The use of the term ground (or earth) is so common in electrical and electronics applications that circuits in portable electronic devices such as cell phones and media players as well as circuits in vehicles may be spoken of as having a "ground" connection without any actual connection to the Earth. This is usually a large conductor attached to one side of the power supply (such as the "ground plane" on a printed circuit board) which serves as the common return path for current from many different components in the circuit." From: http://en.wikipedia.org/wiki/Ground_(electricity) The "large conductor, "ground plane" or "radials" are in the air or in the space. The air or the space are the "infinite source or sink for charge". I assume that you know that a conductor gain/loss the charge in the air/space. But the conductor must be large enough. In your "dipole" one radial is enugh but in a big station must be much more. The same was wrote by Marconi. S* |
#74
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Anyone know where I can find plans for an artificial ground?
"Wayne" napisal w wiadomosci ... # It is not my theory. Somebody wrote: # "H. Horizontal, unbalanced antennas, such as a long wire or random wire, # need an RF Ground wire that should be 10-15% longer than the antenna wire # itself. This is often called a counterpoise. The RF ground wire in this case # can be laid out in many ways, just so long as it does not cross over itself # to form a loop. Indoors, such wires are often run under carpets or along # walls, out of windows, or anywhere else convenient. This wire will often # have large RF voltages on it, so it should be kept away from people or # insulated to prevent contact." From: # http://www.sgcworld.com/radialstechnote.html # Your "dipoles" are "horizontal, unbalanced antennas". The radial or # counterpoise "should be kept away from people or insulated to prevent # contact." It appears that your reference above from SGC contradicts your single radial assertion. For a half wave antenna broken in the center, you claim that the half connected to the coax braid is a radial. If it is a radial, why does it have high voltage at the end, behaving like a dipole? ""Marconi, who discovered if he attached one terminal of his transmitter to a wire suspended in the air and the other to the Earth, he could transmit for longer distances". Each transmittel as a source of AC produces the high voltage at the both ends. If the one end is in the soil you have the monopooe antenna. But next Marconi discovered that the radials are better than the soil. You should understand that 120 radials have lower voltage than one radiator. Also one radial from your "dipole" connetced in series with the shield has lower voltage. Have you posibility to measure the VSWR on the both legs your "dipole"? S* |
#75
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Anyone know where I can find plans for an artificial ground?
Szczepan Bialek wrote:
"tom" napisal w wiadomosci . .. On 5/1/2013 3:47 AM, Szczepan Bialek wrote: You simply do not know that: "In electronic circuit theory, a "ground" is usually idealized as an infinite source or sink for charge, which can absorb an unlimited amount of current without changing its potential." and, But the "ground" you are referring to in this paragraph is NOT the one you are in the next. One is an essentially infinite sink, and the other ignores that property entirely. So you are arguing with yourself here. The both paragraph are wrote by the same Author. Irrelevant. You are incapable of understanding that the word "ground" can refer to several different things. "The use of the term ground (or earth) is so common in electrical and electronics applications that circuits in portable electronic devices such as cell phones and media players as well as circuits in vehicles may be spoken of as having a "ground" connection without any actual connection to the Earth. This is usually a large conductor attached to one side of the power supply (such as the "ground plane" on a printed circuit board) which serves as the common return path for current from many different components in the circuit." From: http://en.wikipedia.org/wiki/Ground_(electricity) The "large conductor, "ground plane" or "radials" are in the air or in the space. The air or the space are the "infinite source or sink for charge". Nope, they are not. You are incapable of understanding that the word "ground" can refer to several different things. I assume that you know that a conductor gain/loss the charge in the air/space. But the conductor must be large enough. In your "dipole" one radial is enugh but in a big station must be much more. Babbling gibberish The same was wrote by Marconi. It doesn't matter a lot what Marconi wrote as a lot of the things he wrote were later discoved to be wrong or only apply in limited situations. -- Jim Pennino |
#76
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Anyone know where I can find plans for an artificial ground?
Szczepan Bialek wrote:
"Wayne" napisal w wiadomosci ... # It is not my theory. Somebody wrote: # "H. Horizontal, unbalanced antennas, such as a long wire or random wire, # need an RF Ground wire that should be 10-15% longer than the antenna wire # itself. This is often called a counterpoise. The RF ground wire in this case # can be laid out in many ways, just so long as it does not cross over itself # to form a loop. Indoors, such wires are often run under carpets or along # walls, out of windows, or anywhere else convenient. This wire will often # have large RF voltages on it, so it should be kept away from people or # insulated to prevent contact." From: # http://www.sgcworld.com/radialstechnote.html # Your "dipoles" are "horizontal, unbalanced antennas". The radial or # counterpoise "should be kept away from people or insulated to prevent # contact." It appears that your reference above from SGC contradicts your single radial assertion. For a half wave antenna broken in the center, you claim that the half connected to the coax braid is a radial. If it is a radial, why does it have high voltage at the end, behaving like a dipole? ""Marconi, who discovered if he attached one terminal of his transmitter to a wire suspended in the air and the other to the Earth, he could transmit for longer distances". For certain types of antennas. Most of the antennas that exist today did not exist in Marconi'e lifetime. Each transmittel as a source of AC produces the high voltage at the both ends. Both ends of what? If the one end is in the soil you have the monopooe antenna. Maybe. But next Marconi discovered that the radials are better than the soil. Only under certain conditions. You should understand that 120 radials have lower voltage than one radiator. Babbling nonsense. Also one radial from your "dipole" connetced in series with the shield has lower voltage. Babbling nonsense. Have you posibility to measure the VSWR on the both legs your "dipole"? This is an idiotic question that shows you haven't the slightest clue how antennas work. -- Jim Pennino |
#77
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Anyone know where I can find plans for an artificial ground?
"vu2nan" wrote in message ... I wonder if I have gone nuts going through this thread! 73, Nandu. LOL, but you must admit there is more traffic on the group than before this thread Wayne W5GIE |
#79
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Anyone know where I can find plans for an artificial ground?
Ian Jackson wrote:
Actually, some of the amusing babbling nonsense does occasionally have a small grain of sense. And even if it obviously IS nonsense, can we always say precisely why it is? There is usually some small bit of reality in the stuff this idiot posts, but from that small bit he always makes giant leaps into the land of nonsense. Ye, we can say why his babbling is nonsense but few have the huge amount of time or the inclination to do so. If a dipole is fed directly with coax, is the power (voltage and current) into each leg the same? If not, why not? Again, if a dipole is fed directly with coax, and if you could insert an SWR meter at the feed into each leg, would the two readings be the same. If not, why not? SWR into a leg has no meaning. You may as well be asking how to remove the bones from ice cream. -- Jim Pennino |
#80
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Anyone know where I can find plans for an artificial ground?
On 5/4/2013 3:12 AM, Szczepan Bialek wrote:
"tom" napisal w wiadomosci . .. On 5/1/2013 3:47 AM, Szczepan Bialek wrote: You simply do not know that: "In electronic circuit theory, a "ground" is usually idealized as an infinite source or sink for charge, which can absorb an unlimited amount of current without changing its potential." and, But the "ground" you are referring to in this paragraph is NOT the one you are in the next. One is an essentially infinite sink, and the other ignores that property entirely. So you are arguing with yourself here. The both paragraph are wrote by the same Author. Yes, but they are not about the same thing. Which you obviously didn't get, because you are using search engines to make your arguments instead of a brain. tom K0TAR |
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