VCA/Mixer in and running!
First time I’ve ever had a module work on the first try. I am most pleased right now.
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With the arrival of my off-brand oscilloscope, I decided to take a step back and asses what is going on with my build. Frankly it feels like more bad news than good. I am going to try to take stock of it all here.
Before going in to each module individually, overall I now realize that many of my toggle switches have been going into my projects upside down. Most switches are “keyed” with a grove on them. In almost all instances it seems this groove needs to be facing downwards. This is a lesson I wish I had learned earlier as it has most likely impacted many of my builds without my being aware of it.
VCLFO: Sample and hold switches. One of them is upside down for sure. The other switch is not keyed so I will have to pull the module to know one way or the other. Most likely this has been leading to a lot of head scratching and wondering why the module acts the way it does. If anyone ever makes an in depth video going over all of this module’s features - I think you would be doing the community a great service.
Filter: The key on the high/low pass DPST switch is facing upwards which to me says it has been inverted all this time - although to my untrained ear it sounds like everything is functioning correctly. If I end up taking it apart I might switch the red LED’s out for something else (this is totally a cosmetic thing to help me color code the LEDs on my system as discussed elsewhere).
Quad VCA Mixer: All eight switches are inverted. This was what really called my attention to my apparent blind spot for flipped switches. Yes, it took me eight identical fails to make me actually notice a problem.
Sequencer: Switches are inverted, but I fixed the problem with wiring. Not that it matters - It turns out that my arcade buttons from ali express are complete and total garbage. This has lead to a lot of drift as it cycles from stage to stage and noise when I press them. More on this in the Fart Box section.
Safety Valve: The switches are installed upside down but as with most stripboard projects the wiring can be ran to make the switch function correctly - which it appears I have done. I am still getting the odd Theremin effect where some ever present “sizzle” noise gets stronger the closer I move my hand to the tube. Hopefully having a scope will help me pinpoint the problem a little easier - once I learn how to use it.
Fart Box: All switches appear to be inverted. This is less obvious and more difficult of a problem to pin down due to the nature of the boxes functionality. In this build more than any other I have noticed that it can be an issue telling what way is “up” on the box’s pcb. This along with the major issues of a bad arcade button has held this project back for quite a long time. I’m am especially sad about this as these arcade buttons were one of the first things I ordered last year and it turns out that all this time they were are major source of headaches. In hindsight, I should have spent more on them. Need to find a new source for concave, illuminated ones - preferably orange. If I have to switch them all out, I might as well pick a color that works with the new scheme.
Buffered Multi: Still having issues with the banks bleeding into each other. Also, it seems to have some unexpected effects on control voltages.
Quantizer: While I have it assembled and the code properly loaded, I think I have numerous wiring issues. Will need a thorough going over.
Clock Divider: While it seems to be finished, it also seems to not be functioning at all right now. I need to print the face plate for it and then test some more.
Phew.
The good news is I feel like I am slowly pinning down where my issues lie. Some of them are due to bad part quality and others are just dumb mistakes on my part. I think I might pull out all of the non-functioning modules in hopes of isolating problems a little easier. However, this brings up storage issues. I think I might need to check the dollar store and see if I can get a Tupperware container or something similar for each one.
Anyway, here is me throwing away all of my remaining arcade buttons.
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If you’re talking about the grove along the threaded shaft, that’s not a “key”.
It is designed to hold the washer with the tab, that tab goes into a small hole (or indent in the big hole) to prevent the switch from rotating, just like the tabs on pots.
You can mount you’re switches the way you like.
At least one good news 
It looks like all your modules are on stripboard, which means your switches have wires.
If one switch works “reversed”, just loosen the screw, turn it 180º, fasten the screw, done !
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It is true for some, but not all sadly. I know its not exactly going to make or break anything - its just annoying.
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If you have some mounted on “commercial” PCBs (or you DLd the gerbers and had them manufactured),
whichever way that groove is, the switch will work the same, and that’s the way the designer of the PCB wanted it to work…
Unsoldering them to resolder them turned 180º won’t make any difference
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Unsoldering them to resolder them turned 180º won’t make any difference
So the Quad Mixer PCB was designed with up to be mute? That seems… odd.
The more I think about this the more unsure of this statement I become.
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kinda were I’m at , have built a bunch of stuff most not working properly some of which I can’t tell because I’m not sure how to hook it up or what actually working is supposed to sound like . have a friend that is a fricking genus when it comes to electronics / music related stuff but because the covid we haven’t been able to hook up .
ON down and OFF up, that’s how I mount my switches, it seems more logical to me, but we don’t all have the same logic 
btw the switch in my home are like that to for light, but it may depend on the country or the electricians ???
Yeah, code for switches is up for on here. It’s funny tho outlets go either way
@eric is right tho, flipping the switch in the footprint won’t do anything. You’d have to flip the wires going into it
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It’s not a vid but all the details fonction. but maybe you have allready seen it.
In doubt it’s here
Taking care of some boring things - but necessary none the less.
Version 1.5! I swapped out the LED’s and replaced some of the pots. This was one of the very first modules I made and at the time I had no idea how important it was to have the type of potentiometers that have a nut to tighten on them. Much more solid feeling now.
Next up I need to permanently mount the second PSU and power bus inside of the case. This means I need to make a new one for testing. I am going to take a stab at the stripboard version:
New arcade buttons are on the way.
Going to put together the K25 A/R EG next so that I can have it, the ADSR and the bounce all next to each other.
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Things are coming along! I have all of the K25 modules pretty much finished up including the sequential switch - though I am waiting on a tayda order for parts for the sub-osc and the glide (and the push buttons for the switch).
I am working on the clock divider now and while there have been a few rough patches, I have been having much success. I’m experimenting with printing name plates for the jack sockets and the results are not bad. I just wish I had an SLA printer now to get some nice sharp edges.
The clock divider itself is working, which is a huge accomplishment for me. Right now the 1/2 indicator LED is double the brightness of the others for some reason and the 1/4 socket and LED are not working at all - but everything else is ticking along just fine. If anyone would like to help sort out the reset push button (that is, adding it into the circuit) - I would be much obliged! Thanks to @juggle for the strip board layout.
The Fart Box is done! I printed my own enclosure for it and had to make shaft extensions for all of the pots. It is a little less sturdy feeling than I would like - but it works. It certainly is an odd (and noisy) beast. I am running into a lot of “well, I hope its supposed to do that”. It is awfully fun to play with and gets a good laugh out of people.
I have both a branches module and a turing machine MK2 waiting to be assembled and kosmoded, but I am resolved to not start on them until I have some of my other more basic things finished up like the buffered mult and the quantizer.
I also need a bench top power supply for testing modules. Testing right now is a bit hair razing as I have to plug them into my actual setup. Not great.
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Ah hah! I knew we talked about this before…
If I am using 12v, what value should R1 be?
15-22k should work. As shown in the schematic, you have 15 V minus a diode drop over 47k+100k, so about 1V per 10k (and 10 V over the 100k resistor). With 12 V, you have 3 V less to play with so need to remove ~30k.
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Boom! Done and done
Also not talked about are my new patch cables, my oceans 11 reverb and the fact that I know how to use the effects return on my mixer now.
And yes, the reset button works perfectly. Thanks to everyone for this!
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Check carefully for any solder bridges. I had a small one that I missed the first few times I checked mine that was causing a similar issue. My 1/8 channel has also failed twice and I’m still not sure why…I can’t find anything obviously wrong with it though. I wonder if it could be the 4024 got damaged when I had the solder bridge…I should try swapping to another and see if it solves it. Just haven’t had much time to mess with my synths the past few months 
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I got it all sorted now. Hopefully you get some time to work on things again soon.
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Infrastructure build! I am currently making a new stripboard based PSU. I need to print the enclosure but my design process stalled - I decided to build a cable tester into it because I just can’t seem to KISS.
I did get a set of helping hands and some head mounted magnifiers. They have already been very helpful.
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Finally progress on my PSU - it seems that some of the traces on my stripboard got cut somehow. Everything seems to be working well - next up is getting the cable tester working. I have the enclosure designed and waiting to print.
I managed to pick up a strange Chorus pedal for 40$. I am running into the usual “is this how it is supposed to work?” situation that comes along with working with audio equipment that I’m not familiar with.
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