Here’s my new build of Phillip David Stearn’s Analog Feedback Machine. I made some minor changes and added two bright LEDs. The circuit is based on an LM324 IC op amp a bunch of resistors, capacitors a transistor, a 9 volt battery and two LEDs. When you touch the two conductive elements you become part of the circuit, creating a feedback loop. If you can’t see the video window click on the image to see a short video.