John Popelish wrote:

Cecil Moore wrote:
Standing wave current phase cannot be used
to measure the phase shift through empty space, wires, or
anything else.

Sure it can. You just haven't yet figured out how to do it.

Here is a hint.
Standing wave current and voltage is not all the same phase.
Go far enough down the line, and there is a change.
How far is far enough?

My comment above is about 1/2WL dipoles and 1/4WL monopoles.
In those antennas, the standing wave current phase is fixed
around zero degrees. It cannot be used to measure delay
through anything.

The 180 degree phase shift in longer antennas doesn't add
any additional information. Since the amplitude is zero
at that point, we already have all the phase information
that we are going to get. We know at the zero point that
the forward current and reflected current are 180 degrees
out of phase.
--
73, Cecil http://www.qsl.net/w5dxp