[TowerTalk] Re: Impact of Reflected Power

[Jim Bradshaw]

Consider that if these reflections are hapenning at the speed of light
(small multiples of).  The echo or delay will be unnoticeable on SSB or CW
especially when dealing with atmospheric conditions that will certainly
introduce more noticable distortions.

Fast scan Television is another story because the modulation technique is
highly sensitive to distortions of the phase relationships.  Ghosting
results.

For SSB & CW,  the distorted waveshape that results from reflections will
still energize the antenna and produce the electromagnetic field.

So the questions remaining are; how much more loss is incurred in all that
makes
up the transmission line including tuner, balun and connectors and how
much power is the transmitter able to make?  These are valid points because
if the transmitter is unable to make full power, it won't be there to lose.
 And even though out of phase relationships of the incident to reflected
waves can't cancel out the power, they will cause higher peak values of
both voltage and current that can increase losses.


Jim Bradshaw, AC6TK

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