Building a Theremin – Rob’s Site

We’re building a Theremin!

This amazing electronics instrument from the late 1800s has featured in songs and movies ever since its invention.

To make music or sound, you don’t actually need to touch this instrument at all. (But to make good music you need to practice)

We’re getting together at the club to make a start on this project, look out for a regular fortnightly session as we build this device.

Here is a rough parts list of the parts you’ll need if you want to build your own theremin. If you can get express shipping then order from ebay, otherwise Jaycar has everything.

Don’t stress if you don’t have everything, we can work in groups on the day and we’ve rounded up all the needed parts.

If you want your own device to take home, we’ve listed what you’ll need below.

Arduino UNO R3 (or similar)
Breadboard
An old speaker or mini speaker
1 or 2x Telescopic antennas OR any wire e.g. coathanger

1x Logic gate chip NAND 74HC00
2x 100k resistors
1x 1k resistor
2x 10p ceramic capacitors
1x 150p ceramic capacitor
1x 100n ceramic capacitor
1x 10uf 10VDC/16VDC electrolytic capacitor
4x male to male wires

Laptop with Arduino IDE

If you prefer your own bench tools, you’re welcome to bring them

Computers in-case you’re not able to bring a laptop
Oscilloscopes
Multimeters
Power Supplies
Power, Wifi, Coffee

Previous build day updates

13th Oct
28th Oct
11th Oct
25th Oct
9th Dec

A great day last Saturday. About 11 people turned up. It was interesting to observe the dynamic; rather than one large group it split into 4 or so groups collaborating within themselves.

Each group chose to use the same basic design using a single free-running LC oscillator with a CMOS logic chip as the gain block. Then an Arduino that measures the frequency, subtracts that from the initial frequency captured at power-up, and generates a tone at that difference frequency.

Dave and Cam troubleshooting
All it takes is a single misconfigured wire
Dani and Forrest installing their hand wound inductor
Cam’s theremin ready for testing
4 slightly different approaches being built
There were some pretty crazy waveforms showing up on the scope

Last time we were mainly working on digital thermins, and this time some of us were keen to keep pushing into new areas. Some of the group decided to start building an analog thermin, given the success they had last time with the Arduino based one.

As this stage, the musical gurus on youtube can still produce a nicer musical sound that we can. But we can make better theramins from random electronic parts in less time.