DIY Mutable Unsuccessful Builds

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Altitude909
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Re: Stages Sanity check

Post by Altitude909 » Mon Jul 27, 2020 5:24 pm

funketek wrote:
Mon Jul 27, 2020 3:41 pm
Not technically an unsuccessful build yet, but I am confusing myself on the orientation of the RECOM DC converter. My understanding is that Pin 2 is the one by the spool and it should be in the lower right corner on the PCB. I have attached a picture of how I am planning to solder it. However, the top view/bottom view of the pin-out has me second-guessing myself. Could I please get a sanity check that this is the right orientation?
Theres a diagram in the silk screen showing the inductor (round thing) and the IC (squareish thing)

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Re: DIY Mutable Unsuccessful Builds

Post by NeolithicElectrophones » Tue Jul 28, 2020 4:00 pm

Edit: Bad pcb, all good now.
Last edited by NeolithicElectrophones on Thu Jul 30, 2020 6:55 pm, edited 1 time in total.

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NeolithicElectrophones
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Re: DIY Mutable Unsuccessful Builds

Post by NeolithicElectrophones » Wed Jul 29, 2020 5:58 pm

Edit:
After scoping, the issue turned out to be incorrect switch routing on the pcb. Did some trace fixing and all is working.

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Re: DIY Mutable Unsuccessful Builds

Post by snowtires » Thu Jul 30, 2020 7:16 pm

Hello everyone, I just finished a Braids build and everything is working, except there is a constant note playing when the output is patched. I replaced the MMBT3904 and the two resistors on the gate jack and that didn't do anything, so I'm about out of ideas. This is the first oscillator in my rack, is this maybe supposed to be how it works? I kind of feel like probably not, but you never know.

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Re: DIY Mutable Unsuccessful Builds

Post by NeolithicElectrophones » Thu Jul 30, 2020 7:37 pm

Unless you're using the internal vca through the menu, it should output a constant tone. Oscillators without internal vca or patched into an external one will just drone. That's how we all do drone patches at least. But just to sort out any confusion, is it just one continuous note that doesn't change when moving the coarse and fine tune pots? That would be a build issue.

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Re: DIY Mutable Unsuccessful Builds

Post by snowtires » Thu Jul 30, 2020 7:40 pm

Thanks for replying before I break something trying to fix it! No, the pitch changes along with the pots, I was just confused as to what I was doing wrong. For once it seems like the answer is nothing!

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Re: DIY Mutable Unsuccessful Builds

Post by NeolithicElectrophones » Thu Jul 30, 2020 7:47 pm

Great! Congrats on your first oscillator build! Be sure to try out the Renaissance firmware on it, it is KILLER. The manual for braids goes into the depth of the menu system and how to set up the internal vca to be triggered. I personally don't think the internal envelope is long enough for pads and such, but it makes for great shorter keyboard and percussive stuff.

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Re: DIY Mutable Unsuccessful Builds

Post by snowtires » Thu Jul 30, 2020 10:17 pm

NeolithicElectrophones wrote:
Thu Jul 30, 2020 7:47 pm
Great! Congrats on your first oscillator build! Be sure to try out the Renaissance firmware on it, it is KILLER. The manual for braids goes into the depth of the menu system and how to set up the internal vca to be triggered. I personally don't think the internal envelope is long enough for pads and such, but it makes for great shorter keyboard and percussive stuff.
Thanks again, I uploaded the Renaissane firmware and lo and behold I can switch the direction of the encoder! Awesome!

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Re: DIY Mutable Unsuccessful Builds

Post by NeolithicElectrophones » Fri Jul 31, 2020 1:01 am

:sb: :party:

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Sat Aug 08, 2020 12:58 am

Hey all, I've got a particularly weird problem, made even weirder by the fact that it's happening on TWO freshly built Rings modules at the same time (one fullsize, one nano). The modules are pretty much fully operational except for the following odd fact: dampness doesn't work (via pot or CV), but the structure attenuator pot modifies dampness. Brightness is similarly non-operational, but the position pot seems to affect brightness. Everything else is fine. I've calibrated both modules, checked for bridges, etc. and I'm totally stumped.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Sat Aug 08, 2020 4:06 am

Check component values and voltages round IC5 and 7

You can calculate the 'static' voltages at the outputs of these and remember to disable the normalisation signal (by inserting an unconnected patch cable into J7)

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Re: DIY Mutable Unsuccessful Builds

Post by sduck » Sat Aug 08, 2020 6:09 pm

This is a dumb question, that I think I've asked before, but can't remember. The ARM chip I've got has two embossed dots - a smaller and a larger one - which one do I line up with the dot on the PCB?

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Re: DIY Mutable Unsuccessful Builds

Post by NeolithicElectrophones » Sat Aug 08, 2020 7:18 pm

I recently had this issue. the larger dot is usually a gate indication mark. The smaller dot on most should be aligned to the bottom left of the text read upright. The smaller dot should be the one that matches the pcb marking.

Sometimes the text is upside down but the smaller dot should always indicates pin1 on stm32 packages.

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Re: DIY Mutable Unsuccessful Builds

Post by sduck » Sat Aug 08, 2020 10:31 pm

Thanks!

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Sun Aug 09, 2020 10:05 am

cnicht wrote:
Sat Aug 08, 2020 4:06 am
Check component values and voltages round IC5 and 7

You can calculate the 'static' voltages at the outputs of these and remember to disable the normalisation signal (by inserting an unconnected patch cable into J7)
Thanks. Everything seems fine there so I have no idea what's going on :bang:

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Sun Aug 09, 2020 10:50 am

Do the wipers of the pots have the correct voltages when you rotate them?

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Re: DIY Mutable Unsuccessful Builds

Post by snowtires » Sun Aug 09, 2020 7:53 pm

I've got a weird problem, I put together a through-hole Braids (https://www.tindie.com/products/jc2046/ ... llator-th/) and it is soooo noisy. I checked and all of the caps are the correct values and soldered correctly, but man this thing sounds like a broken radio. All of the controls work, it's just the noise that is the issue.

The one thing I'm not sure about is that the main STM should have 128Kb of RAM and the one I got only has 64Kb. I'm waiting on another, but would that really be what is causing the problem? RAM is usually a processing speed thing, right, not a sound issue?

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Mon Aug 10, 2020 12:09 am

cnicht wrote:
Sun Aug 09, 2020 10:50 am
Do the wipers of the pots have the correct voltages when you rotate them?
Thanks - I'll check this too.

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Mon Aug 10, 2020 2:13 am

cnicht wrote:
Sun Aug 09, 2020 10:50 am
Do the wipers of the pots have the correct voltages when you rotate them?
The wipers should each have a range of around 0 - 3.3v if I measure from each of the outer pins to the wiper, right? If so, all is fine there.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Mon Aug 10, 2020 3:14 am

aragorn23 wrote:
Mon Aug 10, 2020 2:13 am
cnicht wrote:
Sun Aug 09, 2020 10:50 am
Do the wipers of the pots have the correct voltages when you rotate them?
The wipers should each have a range of around 0 - 3.3v if I measure from each of the outer pins to the wiper, right? If so, all is fine there.
Those values are fine.

Are you seeing these voltages vary at Pin 3 IC4?

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Tue Aug 11, 2020 2:35 am

cnicht wrote:
Mon Aug 10, 2020 3:14 am
aragorn23 wrote:
Mon Aug 10, 2020 2:13 am
cnicht wrote:
Sun Aug 09, 2020 10:50 am
Do the wipers of the pots have the correct voltages when you rotate them?
The wipers should each have a range of around 0 - 3.3v if I measure from each of the outer pins to the wiper, right? If so, all is fine there.
Those values are fine.

Are you seeing these voltages vary at Pin 3 IC4?
So, voltages are varying from just over 0v to around 3v at pin 3 (muxed pots) for everything except damping and position, which are the two pots that aren't responding. I'm assuming this means there's something wrong between the pots and the muxed input?

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Tue Aug 11, 2020 2:57 am

cnicht wrote:
Mon Aug 10, 2020 3:14 am
aragorn23 wrote:
Mon Aug 10, 2020 2:13 am
cnicht wrote:
Sun Aug 09, 2020 10:50 am
Do the wipers of the pots have the correct voltages when you rotate them?
The wipers should each have a range of around 0 - 3.3v if I measure from each of the outer pins to the wiper, right? If so, all is fine there.
Those values are fine.

Are you seeing these voltages vary at Pin 3 IC4?
So, I've fiddled around a bit more and the exact symptoms are are follows:

- all the main pots are fine except damp and position, which do nothing (and also don't affect voltages at pin 3 of IC2).

- all the CV inputs are working fine, including damp and position, except for the frequency attenuator and corresponding cv input, which are not working at all.

- the damping attenuator is acting as the frequency attenuator when nothing is plugged into the damping cv.

- the structure attenuator is acting as the damping pot. The structure cv works, but the attenuator still modifies damping at the same time based on pot position.

So basically it feels like there's something very wrong with IC2 and it's muxxing the signals incorrectly. I've triple-checked for bridges and it seems fine, but the problem must lie somewhere between IC2 and the corresponding pots, right?

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Aug 11, 2020 3:25 am

Yes.

Check for continuity between the pots and IC2.

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Re: DIY Mutable Unsuccessful Builds

Post by aragorn23 » Tue Aug 11, 2020 10:20 am

cnicht wrote:
Tue Aug 11, 2020 3:25 am
Yes.

Check for continuity between the pots and IC2.
Thanks for all your help so far cnicht, it's really appreciated. So when I check continuity between the wiper of the damping pot and pin 5 of IC2 I get continuity, but there's also continuity between this pin and some of the other pots. Should that be the case?

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Aug 11, 2020 3:02 pm

How are you measuring continuity, with the continuity setting on a DMM?

If you're measuring resistance the pots share a common supply voltage and 0V

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