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Old June 25th 10, 09:21 PM posted to rec.radio.amateur.antenna
lu6etj lu6etj is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 143
Default what happens to reflected energy ?

On 25 jun, 08:30, K1TTT wrote:
On Jun 25, 7:46*am, lu6etj wrote:





On 24 jun, 17:54, K1TTT wrote:


On Jun 24, 3:25*pm, Cecil Moore wrote:


On Jun 24, 9:20*am, lu6etj wrote:


Oh, I'm so sorry Cecil, I should have written "However I can not
visualize a simple PHYSICAL mechanism/example to generate
such system in a TL". Anyway, your additional info it is very useful to
me. Thanks.


The physical mechanism is the Z01==Z02 impedance discontinuity with
its associated reflection coefficient, rho. We can see that reflection
on a TDR so it is indeed a PHYSICAL mechanism.
--
73, Cecil, w5dxp.com


don't forget the OTHER physical mechanism that is necessary,
superposition... the ability to add voltages, currents, and fields in
linear circuits and media.


I mentioned same comment in another post. We use superposition
principle in two different contexts. Superposition theorem in circuit
theory, and wave superposition. Wave (traveling) superposition deals
with f(t,x,y,z) and usually with puntual magnitudes, E, H, D, B, etc)
while circuit theory deals with a subset f(t) phenomena and with
integrated magnitudes (V, I). Sometimes that becomes a confused
issue


Miguel


NO, superposition is always the same. *it is the linear addition of
currents or fields in a linear media. *it works the same for circuits
as for em waves.

the big problem are the people who confuse the formulas for adding
powers with adding fields or currents/voltages and forget the phase
terms.

the other big problem is keith who seems to want to separate his waves
into separate time and space variables and leaves out the requirement
that wave functions must be dependent on both space AND time.
basically any solution to the wave equations derived from maxwell's
laws must be of the form f(t-x/v). *this leads him to the erroneous
conclusions he gets from trying to compare his batteries to wave
propagation. *this is the same problem people have with standing
waves, they have separate dependence on t and x, so they can't travel
and can't transport energy.- Ocultar texto de la cita -

- Mostrar texto de la cita -


NO, superposition is always the same


I did not say that things were fundamentally different, I said
"context" it is different, as "substraction" in mathematics, you can
not subtract a natural number bigger from a smaller one in natural
field, but you can do it in integer field, we have to apply (comply?)
contextual rules with such operations. Otherwise I agree with what you
say. 73