7400 competition entry: Discrete Logic Drum machine

Matt built a fully featured Drum machine for the Open 7400 Logic Competition. Check out the video of its operation and his sound generating skills below.

This is a four-channel, sixteen-step percussion synthesizer/sequencer created entirely from discrete logic chips (mostly 74HC-series parts). That’s right, no microcontroller or software of any sort. It was created for the Dangerous Prototypes 7400 Contest in a little over one month of spare-time work.

Via the contact form.

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  1. This is fantastic. No doubt a contender for the overall top prize. The sound generation really demonstrates mastery of the 74xx series, and shows off the power of simple logic chips. Good luck! Definitely think about turning this into a kit!


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