DIY Mutable Unsuccessful Builds

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epijdemic
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Re: DIY Mutable Unsuccessful Builds

Post by epijdemic » Fri Feb 14, 2020 4:46 am

forestcaver wrote:
Thu Feb 13, 2020 10:27 am
Good news! Sounds like the other one has a problem as well! :-)
Yes. I found out when i link 2 Stages and create a 12 step sequencer and have the "jumpy channel 5" module on the right the jump does not "bleed" through to the first output of the left module. the MCU seems to send the correct voltage but the opamp output adds 0.5-1V to channel 5 output (and thus to all outputs of this module)

weirdly both modules are doing this, one more extreme than the other. there might be a wrong resistor value somewhere? i gotta investigate some more with the original eagle file

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forestcaver
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Re: DIY Mutable Unsuccessful Builds

Post by forestcaver » Fri Feb 14, 2020 5:40 am

epijdemic wrote:
Fri Feb 14, 2020 4:46 am
forestcaver wrote:
Thu Feb 13, 2020 10:27 am
Good news! Sounds like the other one has a problem as well! :-)
Yes. I found out when i link 2 Stages and create a 12 step sequencer and have the "jumpy channel 5" module on the right the jump does not "bleed" through to the first output of the left module. the MCU seems to send the correct voltage but the opamp output adds 0.5-1V to channel 5 output (and thus to all outputs of this module)

weirdly both modules are doing this, one more extreme than the other. there might be a wrong resistor value somewhere? i gotta investigate some more with the original eagle file
Yep - sounds like a systematic error. (It sounds like possibly a cap in place of a resistor again tbh....)

funketek
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Re: DIY Mutable Unsuccessful Builds

Post by funketek » Tue Feb 18, 2020 12:59 am

Built Clouds DIY - all 3.3V pins read correctly for power, the -10 reference is also accurate. Was able to successfully flash the clouds firmware to the device. Calibrated at 1V and 3V to note/CV and the LEDs all behaved as the manual indicated. When powering up, the unit lights up the 4 LEDs red followed by orange. Load/save and audio selector buttons seem to work as expected. However, aside from the gain knob and the input/output jacks, none of the CV controls seem to do anything nor do the pots (aside from gain). The output from the output jacks is also very quiet even with gain fully clockwise.

I am getting continuity on 2 of the 3 pins on almost all of the 10K pots, but in some instances it's between pot and ground and others it is pot and 3v3. There is also continuity between the texture and blend pots (middle pins) as well as their corresponding pins on the STM32. Is the best course of action to remove the STM32, clean everything and try again? Or is there a better place to start troubleshooting?

epijdemic
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Re: DIY Mutable Unsuccessful Builds

Post by epijdemic » Wed Feb 19, 2020 3:01 pm

funketek wrote:
Tue Feb 18, 2020 12:59 am
Built Clouds DIY - all 3.3V pins read correctly for power, the -10 reference is also accurate. Was able to successfully flash the clouds firmware to the device. Calibrated at 1V and 3V to note/CV and the LEDs all behaved as the manual indicated. When powering up, the unit lights up the 4 LEDs red followed by orange. Load/save and audio selector buttons seem to work as expected. However, aside from the gain knob and the input/output jacks, none of the CV controls seem to do anything nor do the pots (aside from gain). The output from the output jacks is also very quiet even with gain fully clockwise.

I am getting continuity on 2 of the 3 pins on almost all of the 10K pots, but in some instances it's between pot and ground and others it is pot and 3v3. There is also continuity between the texture and blend pots (middle pins) as well as their corresponding pins on the STM32. Is the best course of action to remove the STM32, clean everything and try again? Or is there a better place to start troubleshooting?
i tried to troubleshoot a faulty trigger input on my SMOG (mini clouds) today and after some reflowing i ran into the same weird behavior you describe. instead of the startup animation i see 4 red and 4 orange leds and nothing works after that, although i can access all options via buttons but thats it. i am not receiving input, nor do i hear anything on the outs.none of the pots seem to work.

have you tried to use blend pot on any of the 4 parameters? for me the leds are not getting coloured according to the pot's angle.

i feel like i might have fried my STM via static charge. unsure how to troubleshoot this one from here. (STLINK util finds the ARM and can interact with it, erase it, flash it, as can the vagrant mutsble environment.. no errors there but the module is in some limbo, does nothing).

funketek
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Re: DIY Mutable Unsuccessful Builds

Post by funketek » Wed Feb 19, 2020 5:15 pm

I cleaned the PCB with isopropyl alcohol really well and then erased/re-flashed the firmware with the ST-link and now I get the chasing LEDs when powering on along with corresponding VUmeter LEDs when feeding it an input. I wouldn't think that just scrubbing the board could have brought it to life, but it seems like it has??

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aseaman
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Re: DIY Mutable Unsuccessful Builds

Post by aseaman » Sun Feb 23, 2020 10:24 am

I'm building a Plaits module and am hoping someone can help shed some light on an issue I'm having. Flashing the firmware was successful as I can toggle the various modes as well as adjust the internal LPG and frequency range. The issue I'm having though is there is no audio out of the output jack. If I run it through a VCA and crank it up I can hear a faint humming but the humming is always the same regardless of what I have plugged into the module.

Any thoughts on what I should be looking for to troubleshoot the issue?

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Sun Feb 23, 2020 11:19 am

Are you getting signals out of the DAC?

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aseaman
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Re: DIY Mutable Unsuccessful Builds

Post by aseaman » Sun Feb 23, 2020 12:53 pm

cnicht wrote:
Sun Feb 23, 2020 11:19 am
Are you getting signals out of the DAC?
I'm currently getting ~3.3mV out of pins 6 and 7 which according to the spec sheet should be the analog output.

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Sun Feb 23, 2020 1:29 pm

That’s much too low - are you measuring with an oscilloscope?

Post some photos of your board.

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aseaman
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Re: DIY Mutable Unsuccessful Builds

Post by aseaman » Sun Feb 23, 2020 7:29 pm

cnicht wrote:
Sun Feb 23, 2020 1:29 pm
That’s much too low - are you measuring with an oscilloscope?

Post some photos of your board.
These measurements were taken with a multimeter as I don't have access to an oscilloscope. When I measure the input into the DAC I get 3.3v -- I also get 3.3v on pin 8 which should be the the analog power supply. Below are two pictures of the board with the latter being a closeup of the DAC (let me know if the quality isn't up to snuff). And again, I appreciate any help on this issue.
You do not have the required permissions to view the files attached to this post.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Mon Feb 24, 2020 2:12 am

It’s going to be difficult to debug without an oscilloscope.

Are you getting a negative voltage on Pin 5 of the DAC (you can measure this where this pin connects to C31)

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aseaman
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Re: DIY Mutable Unsuccessful Builds

Post by aseaman » Mon Feb 24, 2020 6:50 pm

I've been putting off getting a scope but this was all the convincing I needed -- it should be arriving on Wednesday. Until then, I'm not getting a negative voltage on pin 5, instead I'm getting 0.5v

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 25, 2020 2:44 am

The charge pump isn’t working in the DAC.

Check all the pins are soldered correctly as well as its associated components.

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autodafe
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Re: DIY Mutable Unsuccessful Builds

Post by autodafe » Tue Feb 25, 2020 7:59 am

I have a strange issue with my DIY Rings...
Everything seems to work, but the CV/Oct input doesn't seem to...
I connected my KeyStep and tried to calibrate it. Impossible....
If I try to play notes from the KeyStep or from my Per|former, it only plays the same "high pitch" notes for say, midi notes from C0 to C5, then if I go below C0 (like G-1, or C-1) all of a sudden it plays a very low tone...
I don't think it's a calibration issue (I tried to calibrate, no succcess...) but a "input" issue---what should I inspect? the trace going from CV/Oct input or the STM? or whatever else?

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 25, 2020 10:40 am

I'd check the components around IC5b both for solder joints and value.

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Re: DIY Mutable Unsuccessful Builds

Post by autodafe » Tue Feb 25, 2020 11:07 am

cnicht wrote:
Tue Feb 25, 2020 10:40 am
I'd check the components around IC5b both for solder joints and value.
thanks! I was looking at the schematics and then noticed that CV in goes to R14 which is connected to pther Resistors R13 and R15...I'll check those first and triple check the orientation and soldering of that MCP6002. I'll check all soldering joints and components around there! :hail:

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 25, 2020 11:47 am

The output of IC5b should change by 0.47V for every 1.0V change at the V/Oct input, remember IC5b inverts this signal too.

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Re: DIY Mutable Unsuccessful Builds

Post by autodafe » Tue Feb 25, 2020 4:10 pm

cnicht wrote:
Tue Feb 25, 2020 10:40 am
I'd check the components around IC5b both for solder joints and value.
your suggestion was (needless to say) right.
I checked continuity around IC5 (R12-13-14-15 and C14), added some paste, reflowed them....cleaned with IPA. No result
Then I decided to REMOVE all those components and to replace them. BINGO!
Don't know...I probably had some misplaced or incorrect component (or fried?)
(C14 was a 2n2 capacitor but I had only 1206 in size...and probably different specs? I replaced them with a proper one)

Now I have a fully working Rings (or so it seems ;-) )

Thanks a lot - as always

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 25, 2020 6:19 pm

:sb:

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Re: DIY Mutable Unsuccessful Builds

Post by gamblid » Thu Mar 05, 2020 2:04 am

Hey guys, hope somebody can help my with this issue. I built a veils vca and channel 1 and 2 work "ok", but the release time is cut short by a small amount. Channel 3 and 4 don't work well at all, channel 3 sounds muffled and 4 sounds random as hell. I'm starting to think that my VCA chips are on the wrong way around... but how the hell is channel 1 and channel 2 working mostly fine? the pcb doesn't have a polarity indicator so i followed a picture i found online.

Here is a sample of how it sounds, first two is channel 1, next two is ch 2, and so on.

Here is my pcb;
Image

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autodafe
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Re: DIY Mutable Unsuccessful Builds

Post by autodafe » Thu Mar 05, 2020 2:26 am

yeah both 2164 appear to be the wrong way

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Re: DIY Mutable Unsuccessful Builds

Post by autodafe » Thu Mar 05, 2020 2:31 am

Have a look at the .brd files, the "slanted" side is the one with pin 1, like this:

Image

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Re: DIY Mutable Unsuccessful Builds

Post by gamblid » Thu Mar 05, 2020 2:43 pm

autodafe wrote:
Thu Mar 05, 2020 2:31 am
Have a look at the .brd files, the "slanted" side is the one with pin 1, like this:
I successfully flipped one of two of the chips but the second one removed a pad. The chip i successfully flipped just has one channel working sadly.. im actually shocked there's no polarity pointer on the pcb for such an expensive chip. This is awful. Thank you for your help

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Mar 05, 2020 3:30 pm

Look carefully at autodafe's post

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Re: DIY Mutable Unsuccessful Builds

Post by autodafe » Thu Mar 05, 2020 5:47 pm

gamblid wrote:
Thu Mar 05, 2020 2:43 pm
I successfully flipped one of two of the chips but the second one removed a pad. The chip i successfully flipped just has one channel working sadly.. im actually shocked there's no polarity pointer on the pcb for such an expensive chip. This is awful. Thank you for your help
holy cow that's bad!
are you using hot air or standard soldering iron?
as cnicht said, look carefully at the image i posted (it's the "top" 2164)
pads 1 and 8 are not even used, so if you lifted ONE OF THOSE pads you'll have no issues (happened to me sometimes after multiple solder/desolder)
if you removed one of the OTHER PADS, in some cases, they are connected to their neighbour resistor and you can join them with a tiny blob of solder, if not, trace the route in Eagle and then use a piece of thin wire...

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