Art Unwin wrote:
Remember my WL is a closed circuit

Believe it or not, there are reflections at the
feedpoint caused by the Z0 physical impedance
discontinuity. You would be correct only if your
"closed circuit" was a traveling wave antenna.
But if it was a traveling wave antenna, its
feedpoint impedance would be in the hundreds
of ohms which, I assume, it is not. The fact that
your antenna doesn't have a feedpoint impedance
equal to the Z0 of the antenna wire proves that
reflections are present.

W8JI made essentially the same mistake in his loading
coil delay measurements so don't feel bad about it.
--
73, Cecil, IEEE, OOTC, http://www.w5dxp.com