Dave D'Epagnier" <DAVED@ctilidar.com> wrote:
>Steve, why do you want to know the instantaneous forward and reflected
>power? You really wouldn't need this to implement an effective SWR
>protection function, unless you expect that your SWR varies extremely
>rapidly which probably is not the case.
SWR varies extremely rapidly when something in the
transmission-line-antenna system arcs over.
In a high-power radar that I once used, "SWR" sensing was able to shut off
the PA within one microsecond. That system used no microprocessor. I
suspect that it did not compute SWR at all, but responded only to reflected
power. Offhand I don't see why an amp-protection circuit shouldn't be
triggered directly by a reflected-power detector, without benefit of
microprocessor.
-Chuck W1HIS
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