Arduino Theremin

This is a sort of false theremin that turns the distance between your hand and the rangefinder into notes. There are three cap sense pads you can touch to change the key, and the program remembers your most recent song so you can choose to play it back.

The KiCad schematic and layout, along with the the Arduino code, are available at the Github repo. The project is released as open hardware under the CERN v1.2 Open Hardware license.

Using the Theremin Shield
  1. Program the Arduino Uno
  2. To use it, the Uno needs some sort of power, 9V or 5V or whatever.
  3. Press the ‘reset’ button. The red and green lights will blink.
  4. The switch normally sits in the ‘OFF’ position.
  5. Flip the switch to the RECORD position to play and record a tune.
  6. Move one hand vertically between 1 and about 10 inches above the rangefinder.
  7. Use the other hand to press the capacitive sense pads to choose a key.
  8. When you’re done with a tune, flip the switch back to OFF.
  9. When you want to play back the tune, flip the switch to PLAYBACK.
  10. The tune will play once through.
  11. To play it again, flip the switch to OFF and then to PLAYBACK.
  12. To record a new tune, flip the switch to RECORD, which erases the old tune.
Bill of Materials

You can order the boards at OSH Park from this shared project.

You can buy most of the parts from Digikey, except for the rangefinder, which I bought from Adafruit.

Refdes Qty Description Digikey
J1 1 CONN HEADER FEMALE .100” SNGL STR 8POS 952-1823-ND
LED1 1 LED RED DIFF 5MM ROUND T/H 1125-1188-ND
LED2 1 LED GRN DIFF 5MM ROUND T/H 1125-1184-ND
R1,R2 2 RES 220 OHM 1/4W 5% CF MINI S220QCT-ND
R3,R4 2 RES 10K OHM 1/4W 5% CF MINI S10KQCT-ND
RV1 1 POT 10K OHM 1/5W PLASTIC LINEAR 987-1301-ND
SP1 1 SPEAKER 8 OHM .25W 23MM ROUND 458-1124-ND
SW1 1 SWITCH TACTILE SPST-NO 0.05A 24V SW400-ND
SW2 1 SWITCH TOGGLE SPDT 5A 120V EG2377-ND
U1 1 CONN HEADER MALE .100” SNGL STR 40POS S1012EC-40-ND

Note: for U1, one 40-position header is the cheapest option (about $0.50) and you can just snap it apart into the sections you need.

Refdes Qty Description Adafruit
P1 1 Maxbotix Ultrasonic Rangefinder LV-EZ1 Product 172
License

This project is released under the CERN Open Hardware v1.2 License. Click here for more information.