voiding my warranty wheeee

[beefinator]

So my minibrute broke
one of the knobs in the arpeggiator section (/sequencer, if it's in SE mode) stopped working.  The arpeggiator was stuck at maximum swing (which just sounds goofy), and in SE mode, all sequences play back in randomized note order...

Figured I'd share my experience in fixing it, just for others' curiosity...

i opened it up




too many screws...


After some probing with a multimeter and oscilloscope, figured out it was in fact the rotary switch that was the issue.  Desoldered it:


And proceeded to pry open the swi—
oops

well while i wait for the bleeding to stop I heated some soup (cold+snowy day today)


Back to work.  Here's the deal: inside the switch, there's a couple little metal "fingers" attached to the rotating shaft.  These fingers ride along some metal contacts in the body of the switch; turning the shaft makes these fingers connect different sets of contacts.
In the broken switch, these fingers broke off of the shaft.



But lucky me: the shaft piece actually has a second pair of nubs, like the ones the metal fingers were originally fastened with.  (there's a reason for this, i won't explain here)

I turned down my soldering iron to the lowest temperature it could go (still enough to melt plastic), and fastened on the fingers to these new nubs, by melting the tops of the nubs so that they mushroom out over the metal.
one

two


Cool.  One issue though: now the metal fingers don't line up with the original sets of contacts.  The shaft piece has some bits on it that restrict the rotation of the shaft.  I had to remove some of them.  (forgot to take a pic after removing them)


Put the switch back together, soldered it back in, and we're good!  The knob now points in a weird nonsense direction, and it actually detents to 11 different positions (originally 6), but hey, it's usable.  (the extra switch positions all just map to the max swing / random sequence mode)


Screwed the board back in place, put the housing back togeth—
damn


ok, unscrewed all the screws, took out the board, put the button caps in, reassembled everything...
And we're back!


it's all working again   (maybe in part due to my blood sacrifice...)
Only issue/quirk is that the one knob now doesn't line up with the text on the panel.  Oh well, at least the arpeggiator/sequencer is usable again.

[BodoBrute]

A big thanks for that excellent and helpful documentation! I'll somewhen have to replace the faulty filter mode switch in my MiniBrute as well (it's now firmly soldered to low pass). Luckily enough and thanks to Arturia, I have another switch lying at home. And once it's open I'll try and find out what actually happened to the noise circuit (the common "thin and crackly noise" problem) after having used a Korg SQ-1 sequencer.

I hope your finger is better now, btw.  !

[Tom_Bertin]

Super thanks for this post! Helped a great deal! I had the same problem with the swing and the octave knob (or swing and variation in the SE-mod setup).

Extra tip:
It's possible to fix the "fingers" in the original position on the plastic shaft, by melting them into position. That's what I did. Soldering iron was still hot, and so I melted a littlebit of the surrounding plastic (very delicately) over the base of these fingers. It works (for now).

[beefinator]

ha!

Never imagined that not only would someone find this useful >3 years later, but also offer an enhanced solution!

glad you were successful here, it’s pretty fiddly