On Sep 1, 4:11*am, Ian Jackson
wrote:
The impedance looking into the tuner end of the feeder is the impedance
of the load, transformed by length of the feeder, and is also modified
by the loss of the feeder.

That's the result of the 50 ohm Z0-match achieved at the input of the
tuner which is responsible for the transmitter's "happiness". A Z0-
match causes the incident reflected energy to be redistributed back
toward the antenna through a combination of reflection and destructive
interference.
--
73, Cecil, w5dxp.com