Question about "Another look at reflections" article.
On 24 mayo, 22:09, Owen wrote:
On 25/05/2010 07:06, lu6etj wrote:
...
I give the following example: If we load a generator directly with a
resistance of 10 ohms, without any transmission line, there are not
traveling waves interfering, therefore there are not stationary waves,
there is only a impedance mismatch affecting the source voltage żOK?.
If then I load it with a line of half wave finished in the same 10
ohms resitance, the generator "will see" a 10 ohms load, and it will
behave identically as it made it with the original "direct" load.
In both cases there is not reflected power that it can return to the
generator...
I used a similar problem in my discussion entitled "A simple VSWR
analysis without mirrors" athttp://vk1od.net/blog/?p=1259. The article
then goes on to solve a real problem (ie a practical low loss line
rather than the lossless line in the first example, and in your example.
You should find them relevant.
Owen
Well Owen...I have just read your article Ħand you have put me
definitively in a problem! :)
I was never happened to question the Walter's work, I made effort in
learning it being a young student. Now you have put me in a corner and
I will must meditate hard about the issue (with your help,
certainly).
In principle I take a risk to think that somehow it is necessary to
solve "what to do with the reflected traveling wave" because the model
seems to demand "come off of her" somehow that it doesn't return into
the generator, and an explanatory model (and IMHO appropriate) of
making it is to postulate its re-reflection to be consistent with it.
In conventional theory of circuits we simply apply the second law of
Kirchoff because we do not have traveling waves and we accept that the
energy can only flow from the generator toward the load (supposing a
circuit without reactances), there is not anything to come off (in
spanish = deshacerse, desprenderse) :)
I am happened to think that your article combine concepts of both
models, those of basic circuit theory (without traveling waves) and
those of the traveling waves -same as my simple example of course-
with the difference that in mine one I only wanted to point that the
reflected power is not "absorbed" by the pad, and yours is critic of
conjugate mirror model and other postulations.
I think the mixture or combination of models -maybe- it would not be
"elegant" or consistent although it can arrive to the same numerical
results, but I don not dare to advance more than that in my
speculations :)
73
Miguel Ghezzi - LU6ETJ
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