My Monotron is broken.
Yes, my tiny synth had a broken knob. It was pushed from the table and fell face down on the floor. She was the culprit —>
The VCF Cutoff potentiometer was broken, as you can see in my video, it sometimes worked, or only worked when pushed. All this information is in that video so if you’d rather watch and listen, well, watch and listen the video.
With no prior electronics experience but with a history of dismembering all of my childhood’s toys, I took advantage of the Korg’s openness to the modding of all the Monotron models, I found the original schematics on Korg’s website and soon found out I need a specific model of potentiometer: the RK09K1130D61.
This model is found on other Monotrons and on many other Korg machines or other electronic devices. I guess that it doesn’t need a knob cover is a plus.
I did not find one to buy initially online, but I did find the RK09K1130D62, the transparent potentiometer with the LED, if you wanted that instead.
Finding the right potentiometer
So let’s find a potentiometer that fits and has the same specifications and hopefully it behaves the same. So what we need:
- vertical, board mount, kinda like this shape:
- same diameter to fit hole (6mm)
- same length so we can grab it (20mm)
- linear
- 10kΩ
- I guess that’s it?
Like I said this is the first time I did this and I have little knowledge of how potentiometers works. Which should be enough, being so simple.
What else do we need?
I found this potentiometer: the PTV09A-4025U-B103, which looked like a good replacement.
Of course we also needs some other things:
- solder and soldering gun
- a screwdriver
- clippers
- some twezeers would be nice
Let’s just do it, let’s fix the Monotron already
Just take it slow, this is a simple process and I managed to complicate it. The Monotrons are also very explicit inside, everything is labeled. So:
1 – Unscrew the case
2 – De-solder the speakers
3 – Carefully remove the ribbon connection
4 – Remove the broken potentiometer
5 – Solder the new knob
6 – Re-connect the ribbon connection
7 – Solder back the speaker connections
8 – Screw the case back on
That’s it, hope that helped.
Comments are closed