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#11
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![]() "Art Unwin" wrote ... On May 10, 6:58 am, JIMMIE wrote: On May 9, 3:24 am, Szczepan Biaůek wrote: "JIMMIE" ... On May 8, 4:51 am, Szczepan Białek wrote: It seems that at long distances should appear the phenomenon of frequency doubling. See:http://www.rp-photonics.com/frequency_doubling.html Is such? S* The laser must be fed into a non-linear medium for the doubling to occur. The same would be true for RF.Normally the atmosphere and space are considered fairly linear in respect to both RF and light, both forms of EM radiation. Luckily for us this is the case, otherwise all radiation would be multipled to xrays and beyound. The result would probablybe the termination of all life as we know it. Very interesting. May be it take place. You do not analse the intensity after each doubling. My question apply to the two sources emitters (oscillatig dipole) in a lineaar medium. S* The presence of a non linear medium is always required for frequency doubling. The only part of the atmoshere that I know of that meets the qualification is the ionosphere which contains plasma which could act as a nonlinear medium. I suppose that if the signal were powerful enough to produce ionization that a frequency could be doubled.. Jimmie Hi, Let me help you with your problem. You mentioned a cycle which you know is equal to a period or occillation of a radio wave. Let us say that an antenna charges up and then radiates ie half the time or occillation for each action. Now you have decided to apply power to a half wave antenna asnd not a full wave antenna that is occupied in some action all of the time period. Now you have to decide what your half wave antenna is going to do. Charge up only and let the power leak away or radiate without having any power! What you have to do is to imagine a radiator as a tank circuit where you have two energy storage areas, a inductor and a capacitor and for the mom ent free from losses. Thus the energy loads up the inductor which then empties into the capacitor which in turn empties back into the inductor e.t.c Thus only one charge is supplied and no more since the same charge is really not being let go! This is seen as perpetual motion which is an impossibility. Thus if energy is going to be used it will only be expended for half a cycle and then the circuit recharges for the next cycle. Now you should be able to see that a half wave antenna is only capable of working half the time so in no way can you be applying a doubling of frequency motion when you only have a half wave antenna to work with. So S* go back to your study but first replace your half wave antenna and re think things out with a full wave antenna in loop form with a tank circuit in mind and when you have all things in place substitute your half wave antenna and determine what this does to you tank circuit and radiation. Our problem apply to the original Hertz experiment. See: http://people.seas.harvard.edu/~jone...Hertz_exp.html There is: "According to theory, if electromagnetic waves were spreading from the oscillator sparks, they would induce a current in the loop that would send sparks across the gap" In EM waves are produced by the current (oscllator sparks in the Hertz apparatus). One cycle is completed when the current flow to and fro. But there is possible the other theory. Electric waves are spreading from the ends (plates or big balls in Hertz apparatus). Now we know that electrons have mass and are compressible. So at the ends appear and disappear the huge charges. In that case an electric impulse is send when the current flows to (from one end) , and the next when the current flows fro (from the other end). So in one EM cycle are the two electric cycles. So the frequency is not doubled. The electric is twice more. It seems that at long distances receiving antennas should work better at the electric frequencies. BTW, what exactly means "Luxembourg effect" (Brian wrote: " e.g Luxembourg Effect; so doubling is possible.")? S* |
#12
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Szczepan Białek wrote:
Now you have to decide what your half wave antenna is going to do. Charge up only and let the power leak away or radiate without having any power! A 1/2WL dipole is a standing-wave antenna. Believe it or not, ~80% of the steady-state energy on a 1/2WL dipole is not radiated, i.e. as far as total energy is concerned, radiation is a secondary effect. Energy is traveling in both directions at the same time on a standing-wave antenna. At the tip of the antenna, the two energy flows are equal. At the feedpoint, the reflected wave is only ~20% down in energy level from the forward wave - the reflected voltage and current are only ~10% down from the forward voltage and current. The feedpoint impedance of a 1/2WL dipole is the result of superposition of the forward and reflected waves. The Z0 of a 1/2WL dipole using #14 wire at a height of 30 feet is very close to 600 ohms. -- 73, Cecil, IEEE, OOTC, http://www.w5dxp.com |
#13
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On Mon, 11 May 2009 11:35:41 +0200, Szczepan Bia?ek
wrote: doubling is possible.")? No. 73's Richard Clark, KB7QHC |
#14
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On May 8, 4:51*am, Szczepan Białek wrote:
It seems that at long distances should appear the phenomenon of frequency doubling. See:http://www.rp-photonics.com/frequency_doubling.html Is such? S* Your reference seems to explain what you are asking very well. Distance is not mentioned as a factor. JImmie |
#15
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![]() "JIMMIE" wrote in message ... On May 8, 4:51 am, Szczepan Białek wrote: It seems that at long distances should appear the phenomenon of frequency doubling. See:http://www.rp-photonics.com/frequency_doubling.html Is such? S* no distance required, and no antenna required, just put the signal through a diode or other non-linear element and you will get some component at double the frequency. |
#16
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![]() "JIMMIE" wrote ... On May 8, 4:51 am, Szczepan Białek wrote: It seems that at long distances should appear the phenomenon of frequency doubling. See:http://www.rp-photonics.com/frequency_doubling.html Is such? S* Your reference seems to explain what you are asking very well. Distance is not mentioned as a factor. I have found the next: http://books.google.pl/books?id=QSke...P RA1-PA53,M1 There on the page 53 you can find that the medium-wave were disturbed by the long-vave (halve-way between). S* JImmie |
#17
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![]() "Brian Howie" wrote ... In message , Dave writes "Szczepan Bialek" wrote in message ... It seems that at long distances should appear the phenomenon of frequency doubling. See: http://www.rp-photonics.com/frequency_doubling.html Is such? S* not that has been reported anywhere i have seen. this is likely because that at the low amplitudes of radio waves relative to the energies needed to create non-linear effects the medium is close enough to linear that any doubling effect is too small to see. You can get ionospheric mixing of radio waves. e.g Luxembourg Effect; so doubling is possible. You are right. I have found this: http://books.google.pl/books?id=QSke...P RA1-PA53,M1 There on the page 53 you can find that the medium-wave were disturbed by the long-vave (halve-way between). S* |
#18
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![]() "Richard Clark" wrote ... On Mon, 11 May 2009 11:35:41 +0200, Szczepan Bia?ek wrote: doubling is possible.")? No. Here is wrote that it happend: http://books.google.pl/books?id=QSke...P RA1-PA53,M1 There on the page 53 you can find that the medium-wave were disturbed by the long-vave (halve-way between). S* |
#19
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On Thu, 14 May 2009 21:16:06 +0200, Szczepan Bia?ek
wrote: Here is wrote that it happend: Trash is what this reference is called. Someone's diary is not science. If it were not trash, it does not prove doubling. Did you actually read it? It doesn't prove IMD either as there would be a billion reports every day from the presence of the MegaWatt LW stations in Europe. I don't suppose you listen to radio either? MythBusted = Trash and False. 73's Richard Clark, KB7QHC |
#20
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![]() "Richard Clark" wrote ... On Thu, 14 May 2009 21:16:06 +0200, Szczepan Bia?ek wrote: Here is wrote that it happend: Trash is what this reference is called. Someone's diary is not science. If it were not trash, it does not prove doubling. Did you actually read it? It doesn't prove IMD either as there would be a billion reports every day from the presence of the MegaWatt LW stations in Europe. I don't suppose you listen to radio either? Not all MegaWatt LW stations are the Hertz dipole. Such was in Warsow but collapsed. If station has only one end no doubling. Even if it has two the lower must have the same possibilities (tip top of mountain). But the main issue is not doubling. Are you sure that magnetic whirl exist around a wire? S* |
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