How to Build an Optical Theremin
Intro: How to Build an Optical Theremin
What is a theremin? It is an instrument that can be played without being touched. Traditional theremins use antennas and oscillators to sense a person's hand and generate a tone. Ours will use light instead of this, it is not an actual theremin, it just uses similar principles. As a side note, this is my first instructable, so please be nice.
Here is a video of a real thermin:
This is where I learned how to do this:
The original optical theremin
Here is a video of a real thermin:
This is where I learned how to do this:
The original optical theremin
STEP 1: Gather Materials!
This needs very few parts, I made mine for under $20.
Here is what you need:
Two phototransistors
One TLC555 timer IC
One .047 uF capacitor
One 100 uF capacitor
One 1 megohm resistor
One 10k ohm resistor
A battery pack that holds 4 AA batteries
Some wire
A breadboard
A small speaker
Tools:
A wire stripper
Here is what you need:
Two phototransistors
One TLC555 timer IC
One .047 uF capacitor
One 100 uF capacitor
One 1 megohm resistor
One 10k ohm resistor
A battery pack that holds 4 AA batteries
Some wire
A breadboard
A small speaker
Tools:
A wire stripper
STEP 2: Putting It Together
This is a really easy circuit to build. Just make sure that you follow the directions. If any problems come up, I'll gladly try and help you out. Just send me a message.
And yes, the image came from here. It's a fascinating website.
And yes, the image came from here. It's a fascinating website.
STEP 3: The Finished Product and Video
At this point in the game, everything should be working. Congratulations on the build, have fun with it!
88 Comments
see2samuel22 2 years ago
Sigerson 9 years ago
I used a single photoresistor over two photodiodes as this gives it a bit more range. I will later experiment the results from switching out the .47uF capacitor with a .22 uF capacitor as that also affects the tone. I made this before using an electrolytic capacitor for both and it didn't work. I then purchased a set of capacitors that included ceramics and when I used a ceramic for the .47uF, Presto! we had sound.
Sigerson 9 years ago
Also for my picture, the orientation is upside down with regards to the 555 chip. The bottom right of the chip is 1, above it 2 , 3 etc.
schel 10 years ago
s'OK tried this 3 x ...nuttin' I want to use a photoRESISTOR instead. I see I can replace q1 and q2 with a single PR....not gettin' any action. Any ideas on caps or resistors changes to get this werkin'? Power supply is 9v from a bench power. so it's not my battery hehehe
Sigerson 9 years ago
Might be the power? I'm showing 6v on the schematic. Not sure if that's the case. I made it a couple times with no luck as well but I was using two electrolytic capacitors instead of 1 electrolytic and 1 ceramic.
Beergnome 10 years ago
it was messing with me at first, then I discovered that I had the 555 chip pluged in backwards.
Beergnome 10 years ago
Just got done building this circuit and all is working fine.
the fun part about the Photo transistors is that they are sensitive to IR light so you can also use a TV remote to "play it".
pranavpro 10 years ago
ridethetiger1983 15 years ago
thestyrofoampeanut 14 years ago
J-Five 10 years ago
J-Five 10 years ago
I'am going to make this.
leeseibert 11 years ago
Check it out:
https://www.youtube.com/watch?v=BsKRtUCCle4
slinky773 12 years ago
blinkyblinky 11 years ago
12203madman 11 years ago
Arun112 11 years ago
Ghost Wolf 11 years ago
shakespeare1212 12 years ago
GHOSTROSSI46 12 years ago