Cecil Moore wrote:
On Jan 11, 12:06 pm, Gene Fuller wrote:

For a plane wave the E and H fields are
perpendicular for either traveling waves or standing waves. For a
coaxial cable operating in the normal TEM mode, the E field is radial
and the H field is circular around the center conductor. Again, the E
field and H field are always perpendicular. Unless one or both of the
fields are exactly zero, the Poynting vector will be nonzero. It will
have a magnitude and direction.

True for traveling waves. ABSOLUTELY *FALSE* FOR STANDING WAVES. Those
false concepts are the source of your (and others) confusion.You
should have paid attention to my postings of those two very different
equations.

The E and H fields are 90 degrees apart for traveling waves. The cross
product of ExH is the power density in watts/unit-area, i.e. the
Poynting vector. For standing waves, the E and H fields are either in
phase or 180 degrees out of phase. The cross product of ExH for
standing waves is *ALWAYS* equal to zero, i.e. the Poynting vector for
pure standing waves is always equal to zero. Please alleviate your
ignorance on this subject and get back to us. There is ZERO real power
in a pure standing wave. The Poynting vector for a standing wave is
*ALWAYS* zero contrary to what you falsely assert above.

Stating the same thing in voltage and current terms, for a traveling
wave, the voltage and current are either in phase for forward waves or
180 degrees out of phase for reflected waves. Either way, the real
power in the traveling wave is V*I watts.

For a standing wave, the voltage and current are 90 degrees out of
phase. The real power in the standing wave is ZERO! P = V*I*cos(90) =
0
--
73, Cecil, w5dxp.com


Cecil,

That is utter nonsense. Back to school for you. You are confusing phase,
vector direction, phasors, and most everything else. What a mess!

Everything I said above is exactly correct.


73,
Gene
W4SZ