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#41
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Szczepan Bialek wrote:
All physisists (not teachers) are opinion that in space is enough matter to propagate the electric waves. Utter nonsense. You are a babbling idiot. Faraday and Marconi did not go to schools. Faraday attended lectures given by the Royal Institution and Royal Society. Marconi was educated privately in the lab of Augusto Righi, in Florence at the Istituto Cavallero and, later, in Livorno. He also studied under Augusto Righi, a University of Bologna physicist. You are a babbling idiot. |
#42
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"Szczepan Bialek" wrote in message
.. . But the all of you are "the infinite sink" of the real information for me. Not all Amateur radio operators are teachers. Faraday and Marconi did not go to schools. S* Szczepan, you were told in a previous posting (4th June) that Marconi was educated privately. " ... Marconi was educated privately in Bologna in the lab of Augusto Righi, in Florence at the Istituto Cavallero and, later, in Livorno. As a child Marconi did not do well in school ...". Why do you still say that Marconi did not go to school? |
#43
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On Sun, 17 Jun 2012 19:35:34 +0100, "Ian"
wrote: "Szczepan Bialek" wrote in message . .. But the all of you are "the infinite sink" of the real information for me. Not all Amateur radio operators are teachers. Faraday and Marconi did not go to schools. S* Szczepan, you were told in a previous posting (4th June) that Marconi was educated privately. " ... Marconi was educated privately in Bologna in the lab of Augusto Righi, in Florence at the Istituto Cavallero and, later, in Livorno. As a child Marconi did not do well in school ...". Why do you still say that Marconi did not go to school? Rich people had their children educated privately. Public schools at best are mediocre. w. |
#44
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On Sunday, June 17, 2012 11:39:57 AM UTC-5, Szczepan Bialek wrote:
All physisists (not teachers) are opinion that in space is enough matter to propagate the electric waves. I'm not sure about the "all" but indeed in space is enough matter to propagate the EM waves. But it is DARK MATTER, consisting of a different kind of matter with which none of us are presently familiar. Dark matter particles possess a certain observable mass but are clearly not electrons. The density of electrons in free space has been sampled by space probes and there's simply not enough electrons to support EM wave propagation in free space. Do yourself a favor and concentrate on discovering what the "sea of dark matter" is all about. Dark matter is estimated to occupy 84% of all the matter in the universe and one thing is certain - it is not leptons of which electrons are a group member. |
#45
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On 06/14/2012 08:12 AM, Wimpie wrote:
The time varying magnetic field generates an electric field and that is received by the loop. When you screen it completely, it doesn't work, you need the gap. Hello, and one more (and final) time: Electric and magnetic fields by themselves don't propagate, only electromagnetic fields (EM) can transport energy over vast distances. A transmitting antenna has LOCAL (near) electric and magnetic fields but what propagates (i.e. what a receiving antenna sees as the far-field) is an EM field. A receiving antenna has an "effective area" that captures energy in the incident EM wave; what isn't dissipated in the load at the receiving antenna terminals is reflected (scattered) by the antenna (after allowing for any dissipative/ohmic losses in the antenna structure). As economics professor Peter Morici would say "It isn't all that complicated." (But the devil's in the details). Sincerely and 73s from N4GGO, -- J. B. Wood e-mail: |
#46
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On Tuesday, June 19, 2012 5:35:57 AM UTC-5, J.B. Wood wrote:
As economics professor Peter Morici would say "It isn't all that complicated." What a small shielded loop responds to should be easy to demonstrate. We know that a florescent light bulb responds mainly to the electric field because it gets brighter as one moves it from the feedpoint to the top of a mobile antenna. The standing wave voltage loop is at the top of a resonant mobile antenna. The standing wave current loop is at the feedpoint of a resonant mobile antenna. So simply take the small shielded loop and see where it responds the best up and down a mobile antenna. If some people are correct about it responding mainly to the magnetic field, the measured field strength will be highest at the base of the mobile antenna where the standing wave current is the highest. -- 73, Cecil, w5dxp.com |
#47
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On 06/19/2012 11:21 AM, W5DXP wrote:
On Tuesday, June 19, 2012 5:35:57 AM UTC-5, J.B. Wood wrote: As economics professor Peter Morici would say "It isn't all that complicated." What a small shielded loop responds to should be easy to demonstrate. We know that a florescent light bulb responds mainly to the electric field because it gets brighter as one moves it from the feedpoint to the top of a mobile antenna. The standing wave voltage loop is at the top of a resonant mobile antenna. The standing wave current loop is at the feedpoint of a resonant mobile antenna. So simply take the small shielded loop and see where it responds the best up and down a mobile antenna. If some people are correct about it responding mainly to the magnetic field, the measured field strength will be highest at the base of the mobile antenna where the standing wave current is the highest. -- 73, Cecil, w5dxp.com Hello, and one has to make the distinction of whether the receiving loop is in the near or far field with respect to the source of the incident energy. A quick test is to note whether shorting or open-circuiting the terminals of the loop (or any receiving antenna for that matter) has any effect on the current flowing into the terminals of the source (transmitting) antenna. If there's no effect then the receiving antenna is most likely decoupled inductively (magnetically) and capacitively (electrically) from the transmitting antenna. What is seen as available power at the receiving antenna in that case is due to its interception of a propagating EM field. The fact that the orientation of an axis of the antenna aligns with the E or H component of an incident EM field is just a result of the applicable electrophysics. Sincerely, -- J. B. Wood e-mail: |
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