If you get the strobe frequency right, you can match it with a spinning CD. But Remember, the CD rpm slows down as it gets farther into the tracks.
Note: the lable on the CD is just "I LOVE YOU" broken into 4 pieces and evenly distributed into 4 quadrants.
This video doesn't do it justice since the frame rate isn't fast enought to keep up with the strobe. It looks much better in person.
I built the strobe using a 555 timer and a pot for freq adjustment.
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