Owen Duffy wrote:
If the explanation of the discontinuity is that some power is
converted from dominant propagation mode to another mode, and that
those other modes are evanescent, it seems that this analysis of the
impact of the discontinuity considers only estimating the decay rate
of the evanescent modes without estimation of the relative magnitude
of the power diverted to those modes in the first place.

I've always had a rule of thumb that 100 times the diameter of
the coax was enough length to 99% establish the TEM mode so
Kevin's explaination made sense to me.

Apparently, you are not satisfied with Kevin's explaination. Kevin
Rhodes email address is available on Google. The reason not to
publish it here is to avoid spaming his email account.
--
73, Cecil http://www.qsl.net/w5dxp