Gene Fuller wrote:
The entire point of s-parameter analysis is that the "network" can be
treated as a black box, characterized by the various parameters at the
ports. How does that work to analyze what is happening *inside* the box,
such as somewhere along the transmission line?

That's pretty simple to answer, Gene. Simply make
the black box infinitesimally thin so that events
are transparent. Ignorance is immediately alleviated.
--
73, Cecil http://www.w5dxp.com