Looks really amazing! I love the colour composition 
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I tried putting the circuitās output into its CV input and didnāt get much of anything interesting to happen, but then I tried using the inverted outputā¦
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Oooo. Ahhhhh. Wiggly!
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Nice! Excited to see where this goes
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Hey, so I have (slowly) started to build my dfam clone. Today, I got the clock (555 chip) and the sequencer (using the script from @analogoutput ) running.
If calculations are correct the frequency should range from few hertz up to 100 ish. I was afraid the arduino nano would struggle to sync it but it works great. I only had to add a 220r resistor before the +5v of the rotary. It was glitching by adding a weird mode after the random mode.
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I donāt see any way that can happen. The 10 resistors on the switch divide the reference voltage into 10 equal steps (for 11 total switch positions) which should result in ADC values of about 0, 102, 204, 409ā¦ 819, 922, 1023. The code goes from one length/pattern mode to the next at values of 51, 154, 256, ā¦ 870, 973, which should be clean. Specifically, any ADC value above 973 should result in random pattern, length 8; thereās no ADC value that can result in a mode āafter random modeā. And in any case the code always assigns a pattern value (single, inc, exc, double, or random) and a sequence length from 2 to 8, so there should never be a āweird modeā.
Adding a resistor between 5V and the switch will reduce each of the switch voltages by a little. The only thing I can think of is the voltage on the switch (without that resistor) is significantly higher than the 5V at the Arduino (they should be the same), so the last switch position sends a voltage higher than the maximum the Arduino ADC is expecting and I donāt know, maybe that could cause it to produce an unexpected value ā but that would be instead of random mode (which is the last switch position), not āafterā it.
Your switch has only 11 positions enabled, right? (using the stop washer) If thereās a 12th position and nothing connected to that terminal then the rotary switch input would float and that could cause strange behavior. But adding that resistor would not change that.
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I agree that it makes no real sense. I was running this on the breadboard and sometimes it is not running as well as it should. Basically, i had step 7 and 8 flashing randomly when it was behaving strangely. I am sure it will not happen once I solder everything in place. 
And btw, I am using a potentiometer (100k) not a rotary switch as i dont have any left.
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Ahā¦ well, with a 100k pot the voltage maximum is 100k/(100k+220) = 98% of your 5V, so itās only shaving a very little off the top of the range. (The rotary switch as I drew up the schematic is only 10k, so 220R with that would make a bigger change.) I still donāt see how that could cause strange behavior. In fact it seems even harder to understand, since that means you definitely donāt have a floating input.
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Iāve ordered some ASxxxx chip some weeks ago, and they arrived last week, so now itās time to build some modules with them. Iāve started with the AS3340 VCO, and I tried to mix the schematics of @lookmumnocomputer Samās 1222 Performance VCO together with @EddyBergman āReally Good AS3340 VCOā, but made some additional changes according to the great document āAS3340 Funktion und Theoryā by Manfred Lipp. You can find this doc online, but you need to understand german.
I had some problems with the sine wave converter like many others because the Triangle output had some offset, but a cap and resistor fixed it.
The VCO sounds really good, and it seams to be very stable. The Arduino Tuner works great and shows exactly the same note as my āprofessionalā 5ā¬ tuner.
Sam and Eddy, thanks for your great work!
Next Step: Design and etch a PCB and the front panel.
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Fantastic stuff Stef. Iām glad itās working so well. Look forward to seeing your builds progress!
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I have been working on various upgrades:
- I built a wall shelf (middle) for non-kosmo stuff.
- I added inset handles to the top of several of my kosmo cases.
- I added a new phone to the side of my original Kosmo case.
- There is a newish unpopulated kosmo case in the bottom right.
- I converted my outboard gear case (Mondo) to be a counter when not needed (center).
- I added towel racks to the side of Mondo for cable storage (no longer need the chair)
- My Eurorock case is pretty much ready to go. It still needs a handle and I canāt find any good oscillators for it.
- I invested in some IKEA Bror shelving to hold all the stuff. They are STURDY.
- I also finally ordered parts from a bunch of BOMs so I can build some new Kosmo modules! (canāt wait!)
Phew! Time to make some MUSIC!
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looking good , its getting bigger ā¦
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I love the wall shelf! Then again, I also love everything else 
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Whhhaaaou !!!
whatās the big light switch on up of the Kosmo part ?
btw nice new phone 
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Is it not a Big Honking Button (sampler)? I have a PCB of one in the works.
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I think thatās it, itās coming back to me, somewhere in another thread.
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i can comfirm it 
build
and sound
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Yep! Big honking button!
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