In this tutorial, you’ll learn how to build a 555 police siren circuit using two 555 timer ICs.
The 555 timer is a popular integrated circuit (IC) for hobbyists and can be used for a great variety of projects. For this project, we are going to use it to create sound with a twist!
Instead of a “straight” sound, we are going to make the frequency change automatically so it ends up sounding like a wailing police siren.