The TXo has pretty low-tolerance parts in that section to ensure CV output accuracy. I’d be more concerned with the values for the CV being consistent across the outputs - which you may be able to compensate for using the software calibration routines. Any changes to the cutoff of the output’s lowpass filter should be indistinguishable due to it being only a single-pole filter (and thus very gradual).
Given that SMD caps and resistors are relatively cheap (and sometimes less expensive in greater numbers), you might want to grab a bunch and then measure their capacitance to see which one is closer to the target value. While the lot may vary by 5% - there may be some capacitors in there that are closer than others (and within the 1% tolerance).
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I can find 0805 180p 1% caps. I should be able to solder those onto the 1206 pads, I think.
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Absolutely! I’ve done the same myself. 
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I’m about to build my TXO modules -
What’s the purpose of having 110p caps instead of 180p?
I want to build mine to work with the Teensy 3.6 so I understand I need the europower helper as well. Anything else I need to build with the 3.6 in mind?
Thanks
The TXo+ runs at a higher sampling rate; the change in capacitor moves the cutoff of the reconstruction filter to match the rate. This is sorta pointless due to the extremely soft slope of the filter (it is single-pole). So, you should consider it optional. In other words, it is an OCD test. 
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meri
1564
hi @bpcmusic - love your work - i’m not sure if this is the best place to ask but I was wondering if you had updates about availability of modules in your store. i’m really keen to buy a few! hope you’re well x
I’ll copy a bit from my post above from last year:
Still playing catch-up here - so no timetable for when I might get around to building out the TXb and TXn bits I have in various states. I have a tremendous amount of life ahead in the queue at the moment.
For the TXo and TXi, I don’t plan to bulk build any of these in the future again. I have a pipe dream of revamping the design as things that are more easily bulk manufactured. But I wouldn’t be starting that until 2021 at the earliest.
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meri
1566
thanks for the response, sorry I couldn’t find that post in this long thread! i guess i’ll need to look into diy options for TXo and hopefully snatch a TXb at some point!
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mattsb
1567
Given that both hardware and software appear to be open source, I hope this isn’t out of line, but has anyone approached the people who build clones of the Mutable Instruments modules to see if they are interested in building these ? I know the market for Teletype expanders is probably a lot smaller than the market for Rings et al, but if you were one of a very few providers your share of that market would be huge !
buma
1568
@mattsb Afaik, Pusherman is already selling TXO and TXi PCBs and panels. It’s the same community that used to build M.I modules i think they started building these after Teletype was open sourced.
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mattsb
1569
Cool, although I was hoping to have someone build the modules themselves rather than just the PCBs and Panels (not feeling up to doing the DIY myself). I suppose I could find a local builder, but not really what I was thinking of.
Thinking specifically of people like Michigan Synth Works.
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buma
1570
Ah ok, I understand If you join the Pusherman group on Facebook, you might find someone there who will build it for you. Or perhaps directly here on Lines ?
a773
1571
Grrrrr. So today one of my txos stopped working. As expected wiggling the boards made it work perfectly again. However much I appreciate the txos (can’t live without them) the idea of using machine headers to shave off a few mm depth is… not that great. Ordered two pcb/panel sets from pusher man, will use regular headers like I did on the txi, which is rock steady.
I can’t stand the notion of these comming apart on the way to a gig and me having to wiggle pcbs during soundcheck.
Sorry, just had to get it out😏
xeric
1572
Mine weren’t wiggling free very often, but just in case I used a twist tie around the boards to keep mine super secure. Haven’t a problem since
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Yeah - definitely regret not finding space to connect the boards together more firmly. I really tried, but most of the space on the boards was spent trying to simply navigate the pins from the Teensy to the front board. It is such a rats-nest maze. (If I ever get around to a v2 this is one of main things that will change. I imagine it will ultimately look more like the TXn/TXff.)
Zip ties are definitely a good answer - or a bit of string if you want something thinner. I’ve also experimented with 3D printed braces but ultimately abandoned the idea because it wasn’t as effective as the zip tie solution.
You can always just solder the boards together. Makes future repairs a nightmare but turns the thing into a tank.
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XiXora
1574
Ah! That’s a plan.
Mine fall apart by looking at them. I’ll solder them together when I get the chance.
Hopefully, some space for a spacer or something can be found one day.
I found these square-pin, low-profiles female header sockets work well. They’re pretty tight, with standard square-pin pin headers.
They shave a few mm from the overall depth of the module, too. I’ll be using them again, if I ever make up another Radio Music!
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a773
1576
Yeah they look much better, do you have a mouser number?
Manufacturer’s part # is 929984-01-36-RK.
They’re quite expensive, but worth it if you need to reduce the depth of multi-board modules.
