Step sequencer

Posted on Feb 6, 2014

The output of the 4017 is 100% duty cycle. so that means if you have step one and step two on, they will lead right into each other and you`ll have a step that is 2 cycles long. The output of the 555 timer is a 50% duty cycle. The AND gate combines the outs of the 4017 and the 555. The out of the AND is only high when both the 4017 and t

 Step sequencer
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he 555 are high. SO it will go high when you set the step switch (from the 4017 out) on and for half a cycle because of the 555 50% duty. Make sense It`s kind of confusing but relatively simple as far as logic goes. Does this schematic actually work I would imagine there is some propagation delay through the decade counter that will prevent the clock signal from lining up with the pulse from the counter at the AND gates any comments on this is long enough that even if they start a few nanoseconds off it doesn`t matter. In a musical context any delay is completely imperceivable. If the sequencer was running at extremely high frequency it might be an issue. Hi, ive been casually working on designs for a sequencer for quite a while (too long!). I want one to trigger where the piezos normally would on my electric drum. I was after more steps so ive tried (unsuccessfully) to cascade two 4017 ²s. A new thought occoured to me maybe they could be driven by the two outputs of a darlington pair. This would`nt allow the 50% duty cycling thing (which might be a problem) but would be a nice tidy circuit! I am working on a tutorial for Make Magazine right now. It will include step by step directions on how to build one from scratch. I will post the instructions on my site once they are done. casper, thanks for all of this information! 2 questions: will this sequencer allow two channels to be activated at the same time also, can...

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