Cecil Moore wrote:
Jim Kelley wrote:

Since a standing wave can be considered an amplitude vs phase plot
(where both phase and amplitude vary with position) ...

For the standing wave function, I(x,t)=Io*cos(x)*cos(wt),
the phase at any point x, for a particular (t), doesn't
change phase. Set t=0 and vary x to see what happens.
Only the amplitude changes with x. That's why standing
wave current phase cannot be used to measure the delay
through a loading coil.

The term x is the phase of the cosine function, Cecil. The phase of the
standing wave function varies by 90 degrees along the length of a 1/4
wave resonant standing wave antenna.

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