DIY Mutable Unsuccessful Builds

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forestcaver
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Re: DIY Mutable Unsuccessful Builds

Post by forestcaver » Thu Jan 30, 2020 2:32 am

duxcub wrote:
Wed Jan 29, 2020 7:25 pm
forestcaver wrote:
Wed Jan 29, 2020 11:48 am
Not sure I understand the question - it seems banal to just say “use an accurate and precise voltmeter”
(Ideally you want at least a 50,000 count meter for precision - accuracy is another matter !).
Not sure if that answers your question or not....
In his spreadsheet, he has values like this for a 2v reading: 2.03158v.

I’ve never needed a multimeter/voltmeter that accurate. 50,000 count multimeters are $300-500 on Amazon. Is that what I’m looking for? Kinda stinks to pay that much for something I only need for this one application :(
I use a brymen bm869s - ~€200
It depends how accurate you want it! If you want accurate v/oct tracking and want to reliably calibrate a dac to less than 1mv accuracy you need a precise voltmeter. No getting away from it....

But just use what you have - if your dmm is not very accurate or precise, you’ll probably never know how far out you are and it’ll probably get you close enough - depending on your needs and how accurate you want it.... (especially for almost all the use cases of stages).

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Re: DIY Mutable Unsuccessful Builds

Post by duxcub » Thu Jan 30, 2020 5:51 am

forestcaver wrote:
Thu Jan 30, 2020 2:32 am

I use a brymen bm869s - ~€200
It depends how accurate you want it! If you want accurate v/oct tracking and want to reliably calibrate a dac to less than 1mv accuracy you need a precise voltmeter. No getting away from it....

But just use what you have - if your dmm is not very accurate or precise, you’ll probably never know how far out you are and it’ll probably get you close enough - depending on your needs and how accurate you want it.... (especially for almost all the use cases of stages).
I’ll try it with the multimeter I have and see how well it works. I saw that Brymen model suggested when I did a search based on your previous advice. It looks like a good option if I need it. Thanks for the help :)

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Re: DIY Mutable Unsuccessful Builds

Post by Sikkboy » Thu Jan 30, 2020 2:58 pm

Sikkboy wrote:
Mon Jan 27, 2020 12:37 pm
Hello!

I am trying to get marbles build working, but the y,x1,x2,x3 part of the circuit is not changing voltage values. Anyone have a clue as to what it might be?
Any help would be greatly appreciated!
---
4/9

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Re: DIY Mutable Unsuccessful Builds

Post by AlterX » Fri Jan 31, 2020 5:27 pm

AlterX wrote:
Wed Jan 29, 2020 5:18 pm
MI Streams - No MCU activity.

Finished MI Streams last night, powered up, no Life in Bar Graph LEDs and cannot select any modes.

You can add an input audio signal and you can get an audio output which can be (filter tweeked / resonance tuned) :-)

On checking the MCU. All Voltages are good. All Ov are good. All continuity between MCU DAC and Bar Graph check out.
Voltages on Bar Graph are good. Scoped signal outputs from MCU, nothing to DAC or Bar Graph.
All Volts on the board including References are good and in Spec.

The MCU was flashed with the Google Sheets linked Streams Boot loader / Streams Hex files. All checksum report correct.

Have I missed something, or is the MCU suspect or Firmware not running. Is there a updated Firmware .hex file(s).

Ideas from the room pse :-)
31 Jan 20 - Fixed :-)

The problem was the STM32 Supplied and Fitted by me was not the one on the BOM or the Circuit Diagram.
Supplier error :-( headache over. An STM32102 was required for the build, a STM32373 was mistakenly supplied...wtf.
MCU changed as I had stock, tested, calibrated..another thumbs up for Mutable Instruments.

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Re: DIY Mutable Unsuccessful Builds

Post by c0ntr4d1ct10n » Sun Feb 02, 2020 7:50 am

I'm getting some strange behaviour with my Plancks. With the switch set to 10V, and using the mix output, Ch.2 gain is significantly more than the other channels (in fact the other channels only seem to be attenuators and not gain).

With the switch set to 0V, turning Ch.2 gain up will attenuate all other channels.

I have tried the calibration procedure (holding Del while switching power on) but this does not change anything.

Anyone know what the problem could be?

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Re: DIY Mutable Unsuccessful Builds

Post by steviet » Mon Feb 03, 2020 1:21 pm

edit: backward jacks.
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Re: DIY Mutable Unsuccessful Builds

Post by Staticcharge » Tue Feb 04, 2020 4:28 am

I've just finished a Braids build and noticed the ARM is the wrong way, Not before powering it up though...the 4.7K resistor R49.
I've removed and correctly fitted it but ST-link says no, I'm assuming it needs to be replaced. I first fitted it 90 degrees CCW, would I have damaged anything else?
I've had a look at the schematic and I think it should be fine just to replace the ARM but wanted to call on the wisdom of others before ordering a new one.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 04, 2020 10:00 am

Did you place R49?

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Re: DIY Mutable Unsuccessful Builds

Post by Staticcharge » Tue Feb 04, 2020 10:51 am

I did yes.
I powered it up and R49 burnt out, once the MCU had been soldered the right way and R49 was replaced I hooked it up to the ST-Link and it doesn't recongise it with the Jtag either way round.
It's my own fault, it's the last one of five and I rushed it.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 04, 2020 11:33 am

I’d replace R49 first then measure voltages before soldering in a new microcontroller.

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Re: DIY Mutable Unsuccessful Builds

Post by grantharris » Tue Feb 04, 2020 12:45 pm

I recently built a uBurst and its not working properly. When it powers up the freeze light is blinking. Feeding audio into the right channel will cause all the LED's to blink red. No other buttons or knobs seem to have any effect and no audio comes out of either output. Any ideas on what this failure mode is or has anyone seen it before?

I recorded a short video of the behaviour.


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Re: DIY Mutable Unsuccessful Builds

Post by Staticcharge » Tue Feb 04, 2020 12:47 pm

cnicht wrote:
Tue Feb 04, 2020 11:33 am
I’d replace R49 first then measure voltages before soldering in a new microcontroller.
I've replaced R49 and resoldered the MCU the correct way.
Would it of damaged the MCU?

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Re: DIY Mutable Unsuccessful Builds

Post by Staticcharge » Tue Feb 04, 2020 12:58 pm

grantharris wrote:
Tue Feb 04, 2020 12:45 pm
I recently built a uBurst and its not working properly. When it powers up the freeze light is blinking. Feeding audio into the right channel will cause all the LED's to blink red. No other buttons or knobs seem to have any effect and no audio comes out of either output. Any ideas on what this failure mode is or has anyone seen it before?

I recorded a short video of the behaviour.

Post a high res photo of the PCB, component side I'm sure folk can help you once they've been able to cast an eyeball over it.
I had an instance where all LEDs flashed red, firmware flashed fine but there was a short across the pins on the shift register I hadn't noticed on first glance.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 04, 2020 1:18 pm

Staticcharge wrote:
Tue Feb 04, 2020 12:47 pm
cnicht wrote:
Tue Feb 04, 2020 11:33 am
I’d replace R49 first then measure voltages before soldering in a new microcontroller.
I've replaced R49 and resoldered the MCU the correct way.
Would it of damaged the MCU?
I’d keep the current limit on the power supply down just in case

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Re: DIY Mutable Unsuccessful Builds

Post by Staticcharge » Tue Feb 04, 2020 1:29 pm

cnicht wrote:
Tue Feb 04, 2020 1:18 pm
Staticcharge wrote:
Tue Feb 04, 2020 12:47 pm
cnicht wrote:
Tue Feb 04, 2020 11:33 am
I’d replace R49 first then measure voltages before soldering in a new microcontroller.
I've replaced R49 and resoldered the MCU the correct way.
Would it of damaged the MCU?
I’d keep the current limit on the power supply down just in case
To summarize the original issue, the MCU had been solder 90 degrees CCW and once the MCU had been resoldered the correct way the MCU won't allow the ST-link to flash. I'm going to assume the MCU is toast...
I've still got to sit down and do voltage checks on the rest of the board but looking at the schematic it should be fine once the MCU has been replaced, I guess there's only one way to find out.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Feb 04, 2020 1:33 pm

You could also measure the resistance on the various rails to ground.

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Re: DIY Mutable Unsuccessful Builds

Post by grantharris » Thu Feb 06, 2020 3:04 am

So progress, followed shortly by frustration and mild despair. I posted earlier about my trouble with my uBursts build. I took a close look at the board and found a solder short between two resistors. Once removed, the module booted up and everything seemed to be working well.

I unplugged it to put on some of the faceplate hardware, mounted it in my rack, turned it on and now the gain on the audio inputs is extreme. Basically pretty much any audio into either the left or the right channel pegs the VU meter now (wasn't happening before, volume worked well) and its distorted through the output. The rest of the module seems to be working.

Here's a photo of the PCB. It's got to be somewhere in the input circuitry before the audio codec chip. It's just weird that both channels are behaving the same way. Any thoughts? Could both channels of the op-amp have failed in this manner? See anything out of place on the photo?

Such a bummer! I'm a little out of debugging ideas until I get my oscilloscope back from a friend.

On the plus side, I also built a Swirls today and it seems to be working really well :)
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Thu Feb 06, 2020 3:26 am

It’s probable that attaching the front panel has flexed the board and broken a solder joint.

Check soldering with lens/microscope, R57 and R26 don’t look properly soldered for example.

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Re: DIY Mutable Unsuccessful Builds

Post by grantharris » Thu Feb 06, 2020 4:20 am

cnicht wrote:
Thu Feb 06, 2020 3:26 am
It’s probable that attaching the front panel has flexed the board and broken a solder joint.

Check soldering with lens/microscope, R57 and R26 don’t look properly soldered for example.
Thanks for the suggestion! Works now! I did a once over and cleaned up the suspect spots. It turned out to be a cold solder joint on the gain pot. Makes sense that the mechanical stress of me tightening the faceplate could cause that.

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Re: DIY Mutable Unsuccessful Builds

Post by epijdemic » Wed Feb 12, 2020 12:38 pm

Hi, new here.

I recently finished 2 MI Stages with the 0603 conversion from Pusherman. Both modules are not calibrateable because their outputs drift extremely and do not stop to drift even after 30 minutes (voltage drift is around 100-500mV up and down constantly)

On top of all output 5 on both modules jumps about 1 V up even if the sliders are resting at zero (in seqencer mode - orange)

Any ideas?

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Re: DIY Mutable Unsuccessful Builds

Post by forestcaver » Wed Feb 12, 2020 4:22 pm

epijdemic wrote:
Wed Feb 12, 2020 12:38 pm
Hi, new here.

I recently finished 2 MI Stages with the 0603 conversion from Pusherman. Both modules are not calibrateable because their outputs drift extremely and do not stop to drift even after 30 minutes (voltage drift is around 100-500mV up and down constantly)

On top of all output 5 on both modules jumps about 1 V up even if the sliders are resting at zero (in seqencer mode - orange)

Any ideas?
I’ve seen lots of reports of people having placed the wrong passives in the lower area of the board as I dont think anyone has found eagle files and the labelling on the board isnt straight-forward (apparently). Maybe look there ? (Triple checking against the MI files). No idea if this is the issue though... (All of mine are 0402)

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Re: DIY Mutable Unsuccessful Builds

Post by epijdemic » Thu Feb 13, 2020 3:28 am

forestcaver wrote:
Wed Feb 12, 2020 4:22 pm
I’ve seen lots of reports of people having placed the wrong passives in the lower area of the board as I dont think anyone has found eagle files and the labelling on the board isnt straight-forward (apparently). Maybe look there ? (Triple checking against the MI files). No idea if this is the issue though... (All of mine are 0402)
oh wow forestcaver, i used your github for calibration :)

btw. once you read out the -1 and +2v for DAC.. do you already put those settings in and compile for ADC, or can i use a "blank" HEX (meaning nothing in settings.cc yet) for the ADC readout?
this was not clear to me from your notes.

i am aware of some misprint and places the diode/resistor correctly.

i will cross check original MI eagle file with the 0603 conversion, but i really cannot tell where this drift is coming from. my electronics knowledge is limited.

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Re: DIY Mutable Unsuccessful Builds

Post by forestcaver » Thu Feb 13, 2020 3:35 am

epijdemic wrote:
Thu Feb 13, 2020 3:28 am
btw. once you read out the -1 and +2v for DAC.. do you already put those settings in and compile for ADC, or can i use a "blank" HEX (meaning nothing in settings.cc yet) for the ADC readout?
this was not clear to me from your notes..
You need the dac to be calibrated first, before calibrating the adc. (Follow the order in the notes - the output for calibrating the adc relies on accurate dac calibration)
Good luck sorting it out - I’ve seen quite a few people have had similar issues with the 0603 build....

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Re: DIY Mutable Unsuccessful Builds

Post by epijdemic » Thu Feb 13, 2020 4:06 am

forestcaver wrote:
Thu Feb 13, 2020 3:35 am
You need the dac to be calibrated first, before calibrating the adc. (Follow the order in the notes - the output for calibrating the adc relies on accurate dac calibration)
Good luck sorting it out - I’ve seen quite a few people have had similar issues with the 0603 build....
Alright thanks.

Here is something that bugged me during build (because on the other 2 OPamp sections its the other way around) but i trusted the silkscreen print.
The 0603 seems to have a Cap and a Resistor swapped (foto on the left) vs. original MI Eagle on the right.
Image

Is it possible this causes the troubles? Gonna try swapping those and test.

EDIT: HOLY SHIT THAT WAS IT!
C48 and R45 need to switch places!

Swapped those and no more drifting and calibration was a breeze! Now all channels sit at 0.00xV when the pots are down except channel 5, still bumps to 0.2xxxV but that seems to be a different issue.

Gonna write Philip to include a note for the 0603 pcb that those 2 passives need a swap (like in the original MI file)

Super happy now and thanks for clearing up the calibration procedure.

EDIT2: my second Stages module outputs are now shifted aproxx -2V to -1V into negative.. the longer the module is on power the more it creeps towards -1V... i guess there is something else at fault :(

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Re: DIY Mutable Unsuccessful Builds

Post by forestcaver » Thu Feb 13, 2020 10:27 am

epijdemic wrote:
Thu Feb 13, 2020 4:06 am
[
EDIT: HOLY SHIT THAT WAS IT!
C48 and R45 need to switch places!

Super happy now and thanks for clearing up the calibration procedure.

EDIT2: my second Stages module outputs are now shifted aproxx -2V to -1V into negative.. the longer the module is on power the more it creeps towards -1V... i guess there is something else at fault :(
Good news! Sounds like the other one has a problem as well! :-)

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