"Roy Lewallen" wrote
Suppose I have a 50 ohm antenna fed with a one wavelength, 50 ohm
transmission line. No reflected power, no damage.

Now I replace the 50 ohm one wavelength line with a 300 ohm one wavelength
line. For 100 watts delivered to the load, the forward power on the line
is 204 watts and the reverse power is 104 watts. All that reverse power
could do a lot of damage, then?

So I guess I should replace the 50 ohm load with a 300 ohm one. Then there
won't be any reflected power, and the transmitter should be ok. Right?
___________

As you well know, the system change you describe will not remove all
reflected power seen at the output of a tx expecting a 50 ohm load. You
have simply moved the source of the reflection back to the plane of the tx
output connector.

Under your scenario the transmission line is happy, but the tx - not so
much.

RF