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A circuit that requires so little and yet says so much (literally), that’s the Light Theremin. Following our step-by-step photos for our latest Weekend Project, this light-sensitive instrument should take no longer than one hour to assemble once you’ve gathered all your parts. Keep in mind that to successfully make this project, you can use either photodiodes or photoresistors. I’ve personally always appreciated the response from photoresistors, but photodiodes have the unique ability of turning light into actual voltage – how cool is that? Of course, the real beauty of this project is that you can experiment with both, thanks to use of a solderless breadboard. You can swap out components on the fly in order to test your circuit design, or gauge the response of your components before committing to soldering, as demonstrated in Steve Hobley’s excellent video.

Don’t forget that the Light Theremin is officially now part of our Weekend Projects Challenge. All you need to do to win a FREE Maker’s Notebook is complete one of our projects in this series and send us a photo of your build and a story of your experiences.

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See all of the RadioShack Weekend Projects posts (to date)

Nick Normal

Nick Normal

I’m an artist & maker. A lifelong biblioholic, and advocate for all-things geekathon. Home is Long Island City, Queens, which I consider the greatest place on Earth. 5-year former Resident of Flux Factory, co-organizer for World Maker Faire (NYC), and blogger all over the net. Howdy!

  • Anonymous

    I will make this tomorrow at work, and I will do you one better: it’ll be on a PCB!

    • Anonymous

      nice! Wanna open-source your circuit design then let me know, would love to feature THAT in Weekend Projects!

      • Anonymous

        Sure! It will be in EAGLE, 5.11. I don’t think I have that timing chip in our lab…but maybe I can find a close equivalent. I’m sure I can at least get the schematic and layout done and probably mill the board too with our fancy schmancy very expensive ProtoMat H100.

        I’m picturing myself fist pumping with this thing at concerts and stuff, so I shall forego the desktop power supply route.