🚀 go-pugleaf

In article <1992Oct30.155410.505@cho006.cho.ge.com> sant_m@cho006.cho.ge.com writes:
 > 
 > I want to detect a video black signal vs something else.
 > I don't know much about the composite video signal coming out of VCR's.
 > Can somebody help me out here ?  Where can I find more info on how to

 >      The Video sig coming out of your VCR's video jack is very
 similar to standard NTSC (United States) video. There are a lot of very
 specific standards and timings which apply to broadcast signals; I
 would suggest the Electronics Section of your library or asking an
 enigneer at a local station for a Xerox of the standard waveform would
 get what you want.

        Quickly, the sig is 1 volt peak to peak. In most graphic
 representations it is upside-down. 1 volt is the tip of the sync pulse,
 bright white is 0 volts. The pedestal (reference black) is about .33
 volts. But these transitions are occurring thousands of times per
 second; a detector would either have to be synchronized or rely on some
 sort of averaging.

        Please - you finicky purists - I took this from NTC-7 and
        rounded to common values.

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        3  Cumberland, Maine          !nlbbs!paula@uunet.uu.net  3
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