Picture of Arduino Lego Tannerin
The Tannerin is a musical instrument that is played by sliding a marker along the length of a wire or pad. This produces a pure sine wave tone, which can extend over as many notes or octaves as you wish, always in a smooth (i.e. portamento/pitch bend) fashion. It was used on the Beach Boys hit, "Good Vibrations."

With everybody building light theremins at the moment (myself included) I thought I'd better release an Instructable for the Tannerin.
Remove these adsRemove these ads by Signing Up

Step 1: The base

Picture of The base
02 - Connecting nichrome.jpg
03 - The circuit.jpg
04 - The wand.jpg
05 - Schematic.png
Begin by building the longest base possible. When sat in the middle, you should be able to easily reach either end. I built mine from Lego - just because I can. Then stretch a piece of nichrome wire across the entire width, and finish up by tying each end around a screw. This will help dissipate any heat that it gives off. Keep this wire taught. Measure the resistance of this stretch of wire, as this will give you an idea as the range, and granularity, of the instrument. Mine was 176 ohms, across 1.2 meters.

Step 2: The wand

Picture of The wand
Create a "wand" by attaching a long piece of cable to a crocodile clip. This must be long enough to stretch across the entire width of the Tannerin, with a little extra to reach the location where the circuit board will be placed.

Step 3: The hardware

Picture of The hardware
Attach wires to either end of the nichrome wire, and feed into a circuit board. Then attach the end of the marker wire to the same circuit. I'm using breadboard, as shown here. The schematic follows.

Step 4: The schematic

Picture of The schematic
The circuit schematic. You will want to replace the resister with some large enough to limit the current through the nichrome wire (lest it gets too hot), but small enough so there's a noticeable drop in potential when the marker short circuits part of the wire. The Arduino has a 0-1023 range for a 0-5v on its analog inputs. i.e. 5 mv per input entry. So if you want 100 possible inputs along the wire, there must be 0.5v across the nichrome wire.
Coffeebot6 years ago
Nice! I'm getting my first Arduino in the mail soon...and I've always wanted a theremin! I think I know what one of my first projects is going to be :)
so am i :) but my first project is a light follower robot :) wich i can do without an arduino, but it isnt so accurate...
I'm an Elec Engingeering major freshman, and we just made a light following robot, called light spiders, so much fun to play around with!!
tudgeanator6 years ago
Very cool.I'm thinking of doing a similar thing,but using a pot. at the end of the wire and having the 'wand' permanentely attached the the wire ( so when you move your hand it pulls the wire an so turns the pot. Just a thought,as i have so many projects at the moment...
I had the same thought.  I'll probably try it this weekend, I'll let you know my results.
golden226 years ago
how do i write this program?
LinuxH4x0r7 years ago
Cool! Great Instructable! Never heard of this. Thanks Joe