How would you detect lack of a square wave?

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Article #15937

#15937

From: Jim Bogard
Date: Sat, 02 Jan 1993 17:23

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What's the best way to detect the presence/lack of a square wave?
I'm trying to build a 'valid video present' indicator, and I have
some chip I got from DIGI-KEY (number not handy) which strips
horiz/vert sync and provides them seperately.  Now I'm wrestling
with the problem of getting a TTL out from the mess indicating 
what's going on.  Anybody got any ideas?  Or is there perhaps a 
chip which will do this for me and I'm being stupid?

Thanks much.

J-.

-- 
Jim Bogard  (jimbo@socrates.umd.edu)
                                            "Implement now, tweak later."
Tech at large / gigging daemon

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Message-ID: <1993Jan2.172332.21070@socrates.umd.edu>

Path: arc1-ca.pugleaf.net!sparky!uunet!haven.umd.edu!socrates!jimbo

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Newsgroups: sci.electronics
Path: arc1-ca.pugleaf.net!sparky!uunet!haven.umd.edu!socrates!jimbo
From: jimbo@socrates.umd.edu (Jim Bogard)
Subject: How would you detect lack of a square wave?
Message-ID: <1993Jan2.172332.21070@socrates.umd.edu>
Organization: University of Maryland University College
Date: Sat, 2 Jan 1993 17:23:32 GMT
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