The Rest of the Story
On Apr 4, 2:54*pm, Cecil Moore wrote:
Roger Sparks wrote:
Is this the idea you were trying to communicate Cecil?
What I am trying to communicate is that the distributed
network model is closer to Maxwell's equations that is
the lumped circuit model. If the lumped circuit model
disagrees with the distributed network model, then it
is wrong.
The joys of motherhood statements.
Steady-state conditions are identical whether the
ideal transmission line is zero wavelength or one
wavelength. If adding one wavelength of ideal
transmission between the source voltage and the
source resistance changes steady-state conditions
in Keith's mind, then there is something wrong in
Keith's mind.
There was an 'if' there, wasn't there? Do you think
the 'if' is satisfied? Or not? The rest is useless
without knowing.
To me, this is destructive interference at work, so all the
power in the reflected wave does not simply disappear into the
resistor Rs on the instant basis.
90 degrees later, an exactly equal magnitude of
constructive interference exists so it is obvious
that the constructive interference energy has been
delayed by 90 degrees from the destructive interference
energy.
You still have to explain where this destructive energy is stored
for those 90 degrees. Please identify the element and its energy
flow as a function of time.
One advantage of moving the source voltage one wavelength
away from the source resistor is that it is impossible for
the source to respond instantaneously
You have previously claimed that the steady-state conditions
are the same (which I agree), but now you have moved to discussing
transients, for which the behaviour is quite different.
If you want to claim similarity, then you need to allow the
circuit to settle to steady state after any change. Instantaneous
response is not required if the analysis is only steady-state.
If you wish to study transient responses, then the circuits do
not behave similarly.
...Keith
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