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If this old mind recalls correctly a TV station with an undesireable SWR
will not transmit a clear image to its viewers because the delayed re-reflection arrives at the TV set later and casues a ghost or smear. Could you please explain the "Reflected power is a mere fiction." and the smear or ghost? tnx Hank WD5JFR "Reg Edwards" wrote in message ... "Richard Clark" wrote: What you describe as reflection and re-reflection occurs between the mismatched antenna and the tuner that has been adjusted to minimize power returned to the transmitter. The sole function of the tuner is to keep this power from being dissipated by the transmitter (common experience of arcing, denoting a voltage reflection, or thermal runaway, denoting a current reflection). The "virtual" reflection (offered by the tuner) is generally know as the complex conjugate of the remote load, seen at the near end of the line through which it is returning. This means that the line transforms the phase and amplitude of the reflection, and the tuner's job is to invert that relationship to counteract it, and return it to the antenna. There are both wave descriptions of this process, and lumped circuit equivalents. Both work, and both describe the same process from different points of view. One does not negate the other's validity (unless, of course, you attempt to mix the points of view and demand consistency in terms - a frequent rhetorical trap here). There will no doubt be a flurry of denials to this simple example with contortions of logic to match. As for the math, you will find it by the reams, once you've been overwhelmed with the arcana of hyperbolic descriptions of a novel physics that have to proceed its proof. Keep your eye on how your literal points in your question go abandoned with these arcane theories. 73's Richard Clark, KB7QHC ==================================== Dear Richard, you are confusing the matter even further, if that were possible. The only saving grace about your tedius message is that you yourself eventually realise what a load of overcomplicated nonsense it is. Reflected power is a mere fiction. Power which is not radiated from an antenna never actually arrives there. In fact it never leaves the transmitter. All the power which leaves the transmiter is radiated except for that which is lost in the line. It has nowhere else to go! But for the existence of so-called SWR meters, the words 'forward and reflected power' would never enter people's vocabularies. For the few who become involved with such matters, the misleading fiction also appears in the language of mathematics. Names have to be invented in order to discuss mathematical equations in plain English. But there's no reason why they should be propagated, just to confuse, into the real World. The sole purpose of an SWR meter is to indicate whether or not the transmitter is loaded with 50 ohms. ---- Reg, G4FGQ |
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