Introduction: PHYS 339 Final Project: Simple Theremin

About: Physics and applied math student looking to make cool shit

As a recreational musician and a physicist, I've always thought that theremins are the coolest electronic instrument. Their sound is almost hypnotic when played by a professional, and the electronics theory required for them to function is fairly simple and super cool. So, for my final project in my undergraduate electronics class, I decided to build a very simple theremin. I'm not the most straight-forward electrician, so there are a lot of jumbled wires in this rough build. However, I don't really care all that much, because we're living in a global pandemic, and the theremin worked!

Step 1: Supplies and Setup

The components required for this build are fairly simple. They are as follows:

  • Perf Board and appropriate connecting wires
  • 5V battery pack (equipped with 4 AA batteries)
  • 1x CD4093 NAND IC
  • 1x MCP602 OpAmp
  • 2x 100pF
  • 1x 1nF Capacitor
  • 1x 4.7µF Capacitor
  • 6x 10k, 1x 5.1k, 1x6.8k Resistors
  • 2x 10k Potentiometer
  • 1x Antenna (I used a simple copper wire, but a more sturdy antenna would be preferable)
  • 1x Audio Jack

Each of components are pictures above.

Step 2: Schematic

This is the schematic I used. I adjusted this from GreatScottLab's intractable of a similar project. In this picture, you can also see my organizational process. Since I'm a college student, I don't have a nice electronics workstation in my home, so I taped the components to this sheet of paper so I wouldn't lose any of them. Maybe not the most savvy way to approach this build, but I thought it was a good idea!

Step 3: Build Time

I should have taken more pictures while building the actual circuit, but I got so in the zone that I forgot to do that. I simply connected each part of the circuit as shown in the schematic. I used a 5V battery pack (with 4 double A batteries) as my power source, to which various parts of the circuit are connected.