Pulse sensor with indicator LED and HD-1900A
You’ll learn to display someone’s heartbeat visually and mechanically.
While the electronic circuit is usually very straightforward, the “magic” in physical computing projects happens always in the code. So, please see the GitHub link to the BOM, the schematic, and extensively commented code that you can easily adapt and recycle in your own projects. Often, there’s a useful code concept or code snippet that you can use for an entirely different design, because it’s a fundamental principle.
If you want to learn about good soldering, this seven minute vintage video is still the best of them all.