Well, this will do it:
Also took the opportunity to flip the panel into artsy mode:
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Hahaha glad you sorted it out! And I got mine flipped too, but I really like crystals 
Here’s the original photo of the crystal plate (self collected here in Washington). I traced it in inkscape with the bezier*(?) tool to make the art for all the utilities. you can line them up if you have all 5, which nobody does cause two of them don’t work yet 
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Question for the experts:
How bad an idea would it be to change R1 and R2 to 1M?
The idea being to reduce the amount of voltage drop when using 1V/oct inputs with nonzero output impedances. One could of course instead tune the multiples’ gain to compensate (indeed, I have a horstronic. buffmult that’s essentially this same circuit, and that’s what I did), but then one would have to re-tune if using different CV sources with different output impedances, or dedicate a different channel to each.
I think I recall reading that such an increase in the resistances would lead to higher noise, and that there are those who feel the typical 100k input impedance of synth modules is already too high.
Then again I note, for instance, MI’s Links has 1M input impedance on its buffered multiple, and the LMNC 1161 uses non inverting voltage followers with a 10M resistor to ground (but a 100R current limiting resistor outside the feedback loop on the output).
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Well, it’s a low gain circuit, so the noise should be low enough (around 18µV at room temperature in audio frequencies). But 1M is really close to the input impedance of your opamp, and that would cause distortion…
I would just use a simple voltage follower, and with the switched connector you don’t even need an input resistor.
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Maybe a little quad buffer module…
I don’t know if I ended up putting the passive/buffered multiples jacks on the wrong side of the PCB or what (I put them on the silkscreened side) but I ended up with the left buffered input on the bottom and the right buffered input on the top, opposite what the panel shows. Took me forever to figure out why I was getting crazy behavior.
Added:
OK, guess I got the build correct and the panel’s … different?
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What I did was this:
I used my expression pedal interface output as a voltage source, so I could vary it with my foot while using my hands to adjust the trim pots. Instead of measuring the input voltage and then trying to match the output voltage, I measured the voltage difference between the input and the output. With 0V input you get a small (under about 10 mV) difference which is fairly insensitive to the trim pot setting, due to op amp offsets. So I adjusted the trim pot until I saw about the same value with a large voltage input. At that point the voltage difference is small and doesn’t vary when you vary the input. That’s the point where you have unity gain, with a little offset.
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Wow, that’s a huge bummer. Ive actually never used one of the faceplates, instead using the handmade plate I had before I had panels made up. This panel/pcb has like 5 errors 
. On the bright side this is a good way of showing me how much I’ve learned in a short time. Sorry bout that @analogoutput
Did anybody else make this thing? I feel like I sent a few out and thinking about you guys struggling with what should be an easy module doesn’t feel good. I’m going to fix the faceplate and order 5. Analog I’ll send you one in a few weeks if you don’t mind dealing with backwards until then. I’m not really interested in fixing the circuit pcb problems though as I have plenty of multiples now
I’ll try to figure out who got them…looks like @ChristianBloch for sure and maybe @d42kn355 and @popflier
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No problem, @CTorp, all part of the fun! And as you see here, the panel’s not going to be an issue for me. I decided I want all the modules in my new case, Kosmodrome, to have a more or less unified appearance. So I did use your panel, but I made an overlay for it.
Great module. Thanks again!
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@CTorp I have one of these and have built it. It has been in the “Need to Test” box though so I haven’t gotten to that point. Actually all of my Kosmo modules are basically in the “Need to Test” box as I don’t have a case yet…LOL.
What are the other issues with the circuit? Do I need to make any changes to fix them?
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No changes needed, will just not make a whole lot of sense when you go to calibrate it. And that faceplate will be wrong. I’m serious about ordering a fixed panel tho, I want it anyway my homemade one is pretty ugly. I’ll send you out a revision plate at some point!
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I had no trouble with calibration, once I figured out which ends the inputs were on.
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What are you waiting for? Get a couple scrap pieces of 1x2 or something, about a meter long, lay them about 180 mm apart across a couple cinder blocks or piles of books or whatever. Screw the modules into them, hook up power, and get going!
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Yeah, I figured out what was wrong and just rewired my brain to remember it that way 
. Would not mind an updated face plate, though.
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Soldering iron or hot air?
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Oh, hot air for sure
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I know, I know. Time during daylight hours is what I need so I can make noise cutting wood, drilling, etc… The only time I get to work on anything is from 10:30pm - 5am, but with a 1 year old sleeping during those hours I can’t make too much noise. 
I also don’t want anything done half-assed so I’ve been designing the case that I want and will likely have a local CNC cut it for me. Then I can put it together at night. Everything just takes forever to do and there’s not enough hours in a day.
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A reminder that Switched-Multiples can be reversed and two in a modular done in alternating panels is twice as cool.
-Fumu / Esopus
So I built up my CT-182 last night…but…something seems to have gone wrong. Not sure how I messed up this simple of a module but all of the LED’s blew as soon as I switched them on. One literally blew in half. The others just blinked and then refused to emit any further light.
I confirmed that my power header wasn’t backwards.
So I’m left thinking I installed the LED’s backwards…but…they look right to me. short leg with the flat side of the lens facing out (negative to the square pad…which does appear to be tied to ground.)
Any thoughts? I’m assuming I’m missing something big and obvious here.
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