DIY Mutable Unsuccessful Builds

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Sat May 30, 2020 6:55 am

I'm not sure it will.

The dual diode (BAT54S) is there to prevent the Normalisation signal exceeding the supply value, the single diode only gives protection in one direction.

Worth a try though and I'll be happy as you to hear that it works.

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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Sun May 31, 2020 4:46 am

This question is not exactly related to an unsuccessful build. But I didn't want to open a specific thread for such a small question. I hope that's ok.
I'm sourcing slider potentiometer for a MI module. On the datasheet I can see that there is a code for the resistance taper. B1 and B2 seem both to be linear:
https://www.mouser.ch/datasheet/2/54/PTL-777483.pdf
As I understand, B2 will reach maximum or minimum resistance a few mm before the end of the travel.
Unfortunately I don't know how they compare in practice.
Should I prefer one over the other for some reason?
Thanks for your opinion.

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Flounderguts
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Re: DIY Mutable Unsuccessful Builds

Post by Flounderguts » Sun May 31, 2020 12:55 pm

B1 will be more controllable, but in practice they will probably be almost indistinguishable from one another on a module. Get whichever one is cheaper.
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Faye
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Re: DIY Mutable Unsuccessful Builds

Post by Faye » Sun May 31, 2020 2:03 pm

Cool, thanks :)

Dominox
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Re: DIY Mutable Unsuccessful Builds

Post by Dominox » Sun May 31, 2020 3:53 pm

Hey,

I have a Braids with successful boot, the display works and I have sound on the output!

But no input or Poti work!

I have check't the parts around ic7 and ic9 but I found nothing...

With the oszi I get no good wave only like noise...

Any ideas

Thanks Dominic

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Mon Jun 01, 2020 5:15 am

Check soldering round IC4.

Make sure it's connected to the microcontroller.

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Re: DIY Mutable Unsuccessful Builds

Post by stevemensink » Tue Jun 02, 2020 6:18 am

cnicht wrote:
Sat May 30, 2020 6:55 am
I'm not sure it will.

The dual diode (BAT54S) is there to prevent the Normalisation signal exceeding the supply value, the single diode only gives protection in one direction.

Worth a try though and I'll be happy as you to hear that it works.
You were right. I just replaced the BAT54 to BAT54S, and it is not the fix I was hoping for :-(.

I have built a couple of hundred modules in my life so far, never had such a stubborn problem. If anything else comes to mind for debugging these, it will be really appreciated!
Screenshot 2020-06-02 13.16.24.png
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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Tue Jun 02, 2020 11:44 am

Measure the voltages at the output of the op amps which condition the signals from the input jacks. You may need to disable the normalisation signal to do this.

How does it compare to the calculated voltage?

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Re: DIY Mutable Unsuccessful Builds

Post by crawave » Tue Jun 02, 2020 3:22 pm

Hi everyone. I built a Plaits. all right, I loaded the firmware. the module works all, the only thing is that from dac pin 7 no sound comes out. I checked the voltages at the dac and stm, the digital signal between dac and stm is there. does anyone have a suggestion for me? thank you all.

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Wed Jun 03, 2020 2:16 am

Have you placed jack sockets J6 and J7?

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Thu Jun 04, 2020 7:57 pm

Has anyone who has built Swirls (micro Tides) had any power supply issues? I'm on my third attempt and once again, I'm getting low voltages (between 100-500mv) on all reference points.

I'm at a loss.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Jun 05, 2020 1:47 am

Is anything getting hot?

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 2:45 am

cnicht wrote:
Fri Jun 05, 2020 1:47 am
Is anything getting hot?
Nope. Everything is staying cool. Not even a little warm.

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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Jun 05, 2020 3:54 am

Interesting.

Did you check the voltages after you'd placed the regulators and reference components and before you placed the microcontroller?

Are D1 and D2 the correct way round?

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 5:56 am

cnicht wrote:
Fri Jun 05, 2020 3:54 am
Interesting.

Did you check the voltages after you'd placed the regulators and reference components and before you placed the microcontroller?

Are D1 and D2 the correct way round?
I populated two boards (one for tides, one for sheep) in one go (stencil, solder paste and hotplate). I have both D1 and D2 oriented as shown in the Eagle (stripe on the white side).

The attached pic with the color codings are the pathways, the readings from my multimeter (from both boards) and what they are labelled in the Eagle file. Every point on each pathway came out with the same voltage.
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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Jun 05, 2020 6:25 am

Is your DMM set to AC or DC scale?

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 6:39 am

cnicht wrote:
Fri Jun 05, 2020 6:25 am
Is your DMM set to AC or DC scale?
DC.

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Jun 05, 2020 8:07 am

Very strange.

Post some high resolution photos of the board.

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Re: DIY Mutable Unsuccessful Builds

Post by pld » Fri Jun 05, 2020 8:35 am

qmulus wrote:
Fri Jun 05, 2020 5:56 am
The attached pic with the color codings are the pathways, the readings from my multimeter (from both boards) and what they are labelled in the Eagle file. Every point on each pathway came out with the same voltage.
Looks like the silkscreen says -12V right where you're measuring +12V... that's probably important :)

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 2:40 pm

pld wrote:
Fri Jun 05, 2020 8:35 am
qmulus wrote:
Fri Jun 05, 2020 5:56 am
The attached pic with the color codings are the pathways, the readings from my multimeter (from both boards) and what they are labelled in the Eagle file. Every point on each pathway came out with the same voltage.
Looks like the silkscreen says -12V right where you're measuring +12V... that's probably important :)
I've been considering that. The pads along the VCC path say "+VCC" while the VEE say "-VEE". Plus, the 3V3 and 3V3_A pads have a "+" in front of them. Those connect to the VCC.

However, in the Eagle file and on the boards themselves, it shows that the red (-12v) stripe goes the other way.

Could this be a design error, and should I try it the other way and see what happens?

I don't wanna blow anything up.

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 2:48 pm

cnicht wrote:
Fri Jun 05, 2020 8:07 am
Very strange.

Post some high resolution photos of the board.
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cnicht
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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Jun 05, 2020 3:06 pm

I can't see anything obvious.

I've looked at my Swirls and the +12V end of the power connector is definitely at the top of the board.

It still seems from the voltage measurements though, that the diodes D1 and D2 are reverse biased.

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 3:12 pm

pld wrote:
Fri Jun 05, 2020 8:35 am
qmulus wrote:
Fri Jun 05, 2020 5:56 am
The attached pic with the color codings are the pathways, the readings from my multimeter (from both boards) and what they are labelled in the Eagle file. Every point on each pathway came out with the same voltage.
Looks like the silkscreen says -12V right where you're measuring +12V... that's probably important :)
Yup. That was the problem. I went ahead and flipped the ribbon cable around and everything works perfectly now.

Thanks for pointing that out!

:hail:

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Re: DIY Mutable Unsuccessful Builds

Post by qmulus » Fri Jun 05, 2020 3:15 pm

cnicht wrote:
Fri Jun 05, 2020 3:06 pm
I can't see anything obvious.

I've looked at my Swirls and the +12V end of the power connector is definitely at the top of the board.

It still seems from the voltage measurements though, that the diodes D1 and D2 are reverse biased.
I flipped the ribbon cable and everything seems to be working now. I just finished flashing the boards, so I guess that maybe the ribbon stripe on the board is marked on the wrong side...?

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Re: DIY Mutable Unsuccessful Builds

Post by cnicht » Fri Jun 05, 2020 3:38 pm

Diodes D1 and D2 protect the circuitry against reversed power lead connection so if they are soldered with the correct orientation no harm should come to the module.

Glad it's working.

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