Owen Duffy wrote:
people like the "reflected power is dissipated in the transmitter and may
overheat it" explanation... it is easier to swallow.

If the forward current and reflected current are in phase
at the source, it may indeed become overheated due to an
over-current condition.

But just as likely (with random feedline lengths) is that
the forward voltage and reflected voltage may be in phase
at the source and blow out the finals due to over-voltage
conditions.

The two above events never occur at the same time. Over-
current conditions occur at low voltages. Over-voltage
conditions occur at low currents.
--
73, Cecil http://www.w5dxp.com