Using the diodes I salvaged from an old electronic organ, as well as a 1980s Forrest Mims III Radio Shack Engineer’s Mini-Notebook on semiconductor circuits, I made a circuit that converts the digits 0 – 9 (each digit with its own pushbutton) to binary using a four LED readout. I did it quickly, not expecting it to work because I hadn’t tested all the diodes out and because there was so many places to misplace a wire. But it worked on the first try, and I was excited about that!
This isn’t exactly the cutting edge of electronics, considering both diodes made in the 80’s as well as a book printed in the 80’s were utilized for this project, but it’s just fun to make bigger circuits that don’t need computer programming. Check out my photo and explanation. Note that I was pressed for functionality and organized aesthetics, this is rather bad prototyping because as you can see I crossed wires and used all different colors. It’s almost impossible to troubleshoot should you need to.