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Build Like A Pyro!
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Take Me To The Gadgetory!
TTL Logic Beeping Down Counter

Posted October 20, 2011 by Chris

My crazy 7400 logic circuits continue with this week’s parody of a movie prop from Iron Man 2. The circuit built in this project is a beeping down counter and since I didn’t see this classic circuit entered into the 7400contest, I figured there’s time left for one last entry. Just like in Iron Man 2 there’s a little red button to start the countdown, a dual 7 segment led display and a nice ‘beep’ for each count.

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