This is a nice one to have thanx sandelinos 
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Question, are the pots viewed from the back and if so are pots RV4 & RV5 pins left unconnected?
One pin on each is shown connected via a black wire (hard to see against the dark grey background) to GND.
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Gotcha makes sense.
Interesting little compact build, I’m gathering all the intel to put this together. I’m in the sunday solder zone💣
I have had the 4017 sequencer on my to-do list for a long time and, looking at the available designs, this looks like a very nice and compact layout!
I have a question about the LEDs though. Are you sure that the CD4017 can source enough current to drive the LEDs? Looking at the datasheet, it seems that the IC can maybe source up to 4-5mA at 12V, which means that R16-R20 should be specified at 10K or more, making the LEDs very dim. Perhaps it’s better to use transistor buffers for each LED to avoid risking damaging the IC?
R16-R20 are 22k and my LEDs are bright enough. (I forgot to add them to the BOM, but you can see their values in the schematic. I’ll update the BOM later today) I’ll add a note to the page to advise against using old inefficient LEDs.
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22k should do the trick to keep the current down. Thanks!
@analogoutput is right. Pin 1 of each pot needs to be connected to ground with a wire. I’ll see if I can somehow make the wires easier to see on the dark background. They looked fine on my computer screen but they’re also hard to see on my phone screen.
The pots are viewed from the back. You can check the pictures of the real physical module in the bottom of the page to see how they’re mounted.
It depends on the LEDs. If you use so called super bright LEDs, which I prefer to think of as super low current LEDs when used for indicator purposes, 10k is probably too low.
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The stripboard layout on my website has now been updated to make the ground wires more visible, and I added the LEDs and their resistors to the BOM along with a note about the resistor values.
Since there is only one LED lit at a time, why don’t you connect all the cathodes together and put a single current limiting resister between them and ground?
Because I’m not that smart 
Having the resistors on the cathode side of the LEDs worked out nicely for the physical build though, because I could use the anode legs of the LEDs to create a “ground bar” running across the middle of the front panel that I used for all the front panel components’ ground connections.
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Nicely solved indeed!
I’m not sure if my suggestion would be smart 
I asked because I was actually wondering, whether this could cause a problem
Should be fine, if only one LED is on at a time (which is the case here). I did that for my version of Sam’s keyboard sequencer.
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Heya thanks again, gotta love it when it works first try. this was a very easy and compact build . gonna have fun with this one
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Looks great! It makes me happy to see other people build my circuits.
Would it be ok to you if I reposted the picture on my website? I’d love to add a little “others’ builds” section to the page.
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Indeed. I like to see what kind of trouble my ideas have gotten into!
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Absolutely my friend!
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Ken Stone’s Peak/Trough, essentially a slight modification of a 1973 Serge module. The “Peak” output produces the highest voltage among the “peak” inputs and the level of the “Peak” potentiometer, while the “Trough” output produces the lowest voltage among the respective inputs and potentiometer. Can be useful in creating complex modulation sources by combining different signals, among other things.
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