Try moving the cap to before the resistor. I’m not sure you need the second diode either - the diode to ground should limit the -ve voltage seen by the CD4017 clock pin to a single diode drop. I’ve done a circuit where I put a small cap in parallel to the diode to ground to make give the peak some decay and then sent that to a comparator to make it a really square trigger pulse.
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Merci !
a polarized one ? and what value have you used plz ?
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Simple ceramic - 47pF - just to widen the pulse a little. Have you got a scope or something to see the shape? Or just experiment a little, you’ll figure it out 
Cheers,
Jared
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thx i will make some test this afternoon
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Let me know if you can’t get it working, I’ll bring up some schematics when I get off the work PC.
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Yes, the cap and resistor form a high pass filter that blocks the main body of the gate (which is, for a short time, DC, which is the ultimate low frequency) but lets through its edges (which are high frequency content). I find it helpful to think of them as a voltage divider: The cap is like a large resistor for low frequencies and a small resistor for high frequencies, so cap followed by resistor to ground is high pass. And resistor to ground followed by cap, well, isn’t.
I believe you get a cleaner result if in fact you omit the diode to ground and add a pulldown resistor after the series diode.
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in fact my little schem has worked for my 2 others DIY sequencers cited above.
i tested to change the order of the resistor and add a 47pf but nothing better.
After i have some better result with the change of power (adjustable wallwart) 12V initialy, i test with 9V, then 7V and now it “work” : only step 1/2 and 9/10 chain more rapidely
i go to test @analogoutput proposal
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If there’s a resistance to ground downstream of your “little schem” then that’ll make the high pass filter needed, but going into a non inverting op amp or other high impedance load, I’d expect not very good results.
The series diode + pulldown should clean up negative pulses better, but it’ll reduce the size of the positive pulses a little.
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thx for that !
i think this afternoon i’ve tried all the possibility, now i have “everything good” except it jump the 9 step .
i also tested to play with the resistor of the AND GATE between the 2 CD4017 (because i think it is around here that it blocks or jump)
if i increase or decrease this resitor (connected to +) i have :
- it stop at the 9 step
- or it jump the 9 step
i don’t understand because it don’t do this when i use the internal 555 clock.
I will try one or two more things and if it does not work it will remain in the old things not connectable 
f**k , I dropped the deal, i add a switch to select 8 or 16 steps and i know that’s the 8 one work well.
One of the envelope followers is fully wired now.
It’s too late in the evening to do some serious testing today. So far using the hinge to connect the 2 boards works nicely.
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Hi there! I just finished designing & building a random trig generator.
1 trig IN and 5 trig OUT with each one a knob for its chance to appear.
I will provide schematic & code soon.
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Well I have not solved my problem of step 9 which jumps on this sequencer.
I ended up adding a switch to select 8 or 16 steps.
It will work well in 8 and 16 with the internal clock, but will work well with an external clock only in 8 steps.
So to test it I pulled out some bending toys.
it took me back a few years but it was fun.
I also have my Furby that I would like to rework a little, but finished the old stuff for now, the paint of my new case is dry, I added small feet under, the hook for the CB microphone on the side and now I have to fix the power inside 
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I also thought about the “planification”, so that the place of each module is practical for the use.
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I managed to get this Uraltone mixer diy-kit working on the first try. Or almost, there was couple of mistakes in the instructions, I spotted all but one of them during the building process, and the last fix was just to turn one diode around.
Kind funny mixer, it is based on a single CD4049 chip and has even has switchable clipping diodes on every channel. It’s like a mix between a mixer and a multiplayer distortion pedal. But four mono input channels with effect-insert and clipping and stereo out. All the channels are normalized to one on their left if there is no inserted plug, so it’s easy to split signal to multiple places from the insert-outs. And there is expansion port for six channel extensions. I think that 61 € for this kit was actually quite cheap, even if the instructions were a bit mess.
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Are your cases more or less the same in terms of the modules they contain? Is every case “one synthesizer voice” so to speak?
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Do you have a stripboard layout for the 16 Step 4017 sequencer? Or a brief explanation of how to get the second 4017? That would be awesome!
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All my cases are the same size (80 / 40cm) and contain 16, 20,18 and this one 17 I believe.
And yes i like to put VCO, VCF, VCA, ENV, MIXER, MULTI and LFO in each case 
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