Jim Kelley wrote:
That's true only if you assume the desired feedpoint impedance must be
the lowest possible value. And I think, as you have pointed out on more
than one occasion, the current maximum is not usually located at the
feedpoint, where it would otherwise be if the current minimum is located
90 degrees away.

The standing-wave current envelope on an ideal
transmission line is sinusoidal and the "current
maximum" is the current anti-node in the sinusoidal
envelope at which point the voltage is in phase
with the current. A loading coil is not an ideal
transmission line and its "current maximum" is not
caused by standing waves. The "current maximum" in
the coil is caused by adjacent coupling between the
coils and does not occur at a purely resistive point.

The current envelope at:

http://www.k6mhe.com/n7ws/LoadedAnte...s/image003.gif

Is clearly not sinusoidal. Although not shown, the
voltage at the current maximum in the coil is not
in phase with the current so in this case, the
"current maximum" is not a pure resistance, is
not the current anti-node point, and is not the
resonant point. The current at the bottom of the
antenna is in phase with the voltage and the feedpoint
impedance is purely resistive.

The coil puts a hump in the current which causes
the current envelope to deviate from sinusoidal.
--
73, Cecil http://www.w5dxp.com