I wanted to make a metronome and decided on the venerable “555” chip. In this case I used an LM555CN. I had all components needed except the IC itself, so I ordered a handful (they are only about $0.75/each) and started the process. This was my first time playing with a 555, and it was great fun!
I started with this circuit from Jameco. Then I breadboarded and made changes until I was happy. The original circuit gave roughly 25-550 BPM which was pretty wild – standard metronomes are 40-208 BPM. My circuit as adjusted gives me 35-200 BPM which is close enough for my purposes.