Cecil Moore wrote:


Reflected power doing damage is an overly simplistic
way of viewing things. The reflected wave is capable
of causing damage without giving up any of its energy.
It is not the energy in the reflected wave, per se,
that causes the damage. It is the interference pattern
established by superposition of the forward wave and
the reflected wave that causes the damage.

If the reflected voltage arrives back at the source
in phase with the forward voltage, that constructive
voltage interference can cause an over-voltage condition
that blows the finals. This over-voltage condition actually
reduces the dissipation in the finals because it is
accompanied by a destructive interference, reduced-current
condition. The finals are actually cooler than normal
when the over-voltage begins to fry them.


Cecil,

Ya know, it is possible to simply add and subtract voltages. It is not
required to determine an "interference pattern". Solid state electronics
are damaged by high voltage or high power dissipation (or both). No
"interference patterns" required.

Perhaps the manufacturers could add exactly the correct length of
transmission line inside the transceivers so that the wrong kind of
interference could never occur at the finals.

8-)

73,
Gene
W4SZ