> Hi Robert,
>
> Thanks for the info. I am going to gate the comparator by simply having my
> code (PIC, of course :-) just reject the input during sync periods (I will
> have an LM1881 sync separator in the circuit to tell the PIC when the sync
> is happening). I'm not sure what you mean by "clamp", though. If you mean
> just limit the video signal swing, I don't understand how that would
> achieve what you are talking about.
>

Video is normally AC coupled.  Clamping, also called DC restoration,
rebiases the signal so that the sync tips are at a known voltage.

Bob Ammerman
RAm Systems
(contract development of high performance, high function, low-level
software)

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