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Old January 3rd 08, 07:35 PM posted to rec.radio.amateur.antenna
Keith Dysart[_2_] Keith Dysart[_2_] is offline
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First recorded activity by RadioBanter: May 2007
Posts: 492
Default Standing-Wave Current vs Traveling-Wave Current

On Jan 3, 2:15*pm, Cecil Moore wrote:
Keith Dysart wrote:
Good answers. Exactly as I expected. Now please
explain the applicability of EM waves to the
state of an open circuited line excited with a
step function, especially after it settles to a
constant voltage (where only an E field will be
present).


Before it settles to a constant voltage, there is
acceleration of electrons that results in an EM
photonic wave.

After it settles to a constant voltage, there is
no acceleration of electrons and the EM photonic
wave disappears.


So when the edge of the step is travelling towards
the right, is there an EM wave to the right of the
step, to left of the step, at the step, or all three?
Similar question for when the step is travelling
back to the generator?

When the line has settled, how do you add the forward
and reflected wave to compute the voltage on the line,
or does the disappearance of the wave mean this is
now impossible?

If only the step itself has an EM wave, how are
voltages computed using reflection coefficient after
the step has reflected from the open end?

...Keith