Keith Dysart wrote:

w5dxp wrote:
The impedance seen by the reflections
is the V/I ratio of the source.

But what a surprise, that is 450 Ohms. Try plotting it. Compute
the slope.

It is 450 ohms under no load conditions. It drops when
one adds the load. Please read w2du's web page to find
out why the reflections do not see 450 ohms and so are
re-reflected.

http://www.w2du.com/r3ch19a.pdf

Sure, why not? Just for fun let's do the Norton model for the
generator.

Please choose a real world source.
--
73, Cecil http://www.w5dxp.com