<=Main Page A True Theremin
Still waiting for that first builder to start a discussion!
Note: PT1 & PT2 & PT3 are photo-transistors which respond better than a single LDR light dependant resistor.
Verify PCB connections to schematic above, let me know of any errors? Mouser list needs update.
This layout matches the enclosure on the Mouser List - TRS jack can mount in either direction
PT3 & LED1 mount in 5 mm terminals facing away from the board. Then insert PT3 & LED1 and fold them over the top of the terminal so they point at one another. Add the light blocking black tube which is now about 1/2" above the board. Bending the black tube at the center is what controls the volume response. If you want to etch this pcb below contact me in my Chat Forum and I will email the iron-on PDF.
- You get to think up the best method for Light Control Interaction or Electro-Theremin mechanics -
I added pads in front of PT1 & PT2 for a Potentiometer, this is for a Electro-Theremin/ Tannerin mechanical add-on.
You might need a black plastic sleeve around the phototransistors to block the light coming from the sides. This will make the light exposure more directional toward the phototransistors front lenses. The photo-transistors are set back when using the black enclosure.
The Audio Output is taken from a 1/8" (3.5 mm) stereo jack into your amp or computer.
The AAA six volt battery pack will last for years, even if left on! The current drain is under 4 ma.
I will make a PDF print-out so you can iron it on and etch your own circuit board. This homemade pcb method is a skill you should develop. If there is a lot of interest in this project I will get some commercially made PCB's in the future and furnish the black rubber tube.
Youtube video on PCB etching
Expand Your Imagination
explore this project you might be on the cutting edge of something original.
Post your results in my Chat Forum. Start a thread and title it "I Want To Make the Opto-VCO board". Come join me for some basic talk! If you have an idea that would improve this design, share with everyone your creativity.
If you develop your own version of this design and post to YouTube, I will be happy to post a link here.
Good Luck from oldtemecula
Sound sample.mp3 using a potentiometer, now to figure out the best mechanical movement, right and left is un-natural.
If you want to etch the pcb for this project contact me in my Chat Forum and I will email the iron-on PDF.
One click $25 Mouser Parts List - This list has two Potentiometers to get you results.
I will advance my build using the Lazy Susan or Pendulum approach which does not use the Pot.