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MS-20 Voltage Controlled Filter for Cheap

What you need:
All the parts for this build
A clean, well-lit working surface
Your soldering iron
Nice solder
Pliers, wire strippers, tweezers, whatever
A large hunk of poster putty to hold your work in place
This Instructable!
Remember, youll need a bipolar power supply to run this circuit. Mounting it to a panel and in an enclosure is up to you. If you want to see how I do it, in tin cans, check out my video about that on Youtube. Search for ozerik — thats me.

This project is based on a lightly modified version of Ren Schmitz’ version of the very well-regarded Korg MS-20 VCF. This circuit has so much potential for modification, but the purpose of this project is to let anyone with enough patience and dexterity build themselves a pro-quality VCF module for literally a few dollars.
Find Ren’s project here

My own schematic is here

BOM (Bill of Materials)
(all the parts you’ll need)

1 x TL074 quad op amp
1 x LM13700 dual OTA
2 x 2N3906 PNP transistors
2 x green LEDs 2 x 100K potentiometer
1 x 470K resistor
2 x 100K resistors
7 x 10K resistors
1 x 4.7K resistor
One more resistor, from 2.2K to 20K… see text!
4 x 220R resistors
1 x 1uF electrolytic capacitor
1 x 100nF ceramic disc capacitor
1 x 4.7nF ceramic disc capacitor
2 x 1.5nF film capacitor”

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