Richard Clark wrote:
As modified, the current slope reveals this is no longer a traveling
wave antenna (but it never was anyway). This can be remedied by
shifting the last load (the apparent transmission line load) to 750
Ohms.

Duhhhhhhhh! When you changed the conditions, you changed
the characteristic impedance. The reason for your confusion
is obvious below.

This, of course, improves nothing in performance.

This is not a performance issue. This is a current phase
issue. The purpose for the existence of that EZNEC file
is to illustrate traveling-wave current - nothing else.

After all, who ever heard of a traveling wave transmission line?

Who indeed? Richard, FYI, a transmission line terminated
in its characteristic impedance *IS* a traveling wave
transmission line. Do you understanding the meaning of
a "flat" transmission line? A flat transmission line *is*
a traveling wave transmission line. Here is one modeled
in EZNEC. Download and click on "Load Dat".

http://www.w5dxp.com/stub514R.EZ

Why is the ignorance level about traveling waves so high
on this newsgroup? It's the result of those inadequate
lumped circuit models.
--
73, Cecil http://www.w5dxp.com