Tom Donaly wrote:

If a magnitude can, by itself, contain phase information, why
do we have to specify the angle in a phasor?

It looks like Cecil is trying to use "phase" as a function of position,
of the envelope of a standing wave rather than the time phase of the
total voltage or current which brings about the standing wave. This
makes it possible to keep the simple topic suitably muddled and enhances
the opportunity to misquote.

As I pointed out some time ago, the envelope of a standing wave isn't in
general sinusoidally shaped. At the one extreme of a matched load, the
total current or voltage vs position function is a straight line, and
there is no standing wave. At the other extreme where there's a complete
reflection, the function is sinusoidally shaped. The current on an
antenna falls into neither category, although the distribution on a thin
antenna is nearly sinusoidal. In between the two extremes, the shape of
the total current or voltage vs position function (that is, the envelope
of the standing wave) is neither straight nor sinusoidal, but can be
described with hyperbolic trig functions.

You can of course divide the period of any periodic function into 360
degrees or two pi radians and call the point along it a "phase" relative
to some arbitrary reference. In the case of a standing wave's envelope,
doing so doesn't generally accomplish anything useful. But it seems to
be providing fodder for imagining great and wonderful insights about
physics. And it certainly is useful in keeping a meaningless argument
going by interpreting "phase" to mean either time phase or the
positional "phase" of a standing wave envelope as necessary to keep the
discussion from proceeding on a linear and logical track.

Roy Lewallen, W7EL