I bought this smoke and carbon monoxide detector several years ago, and it’s been doing its job just fine ever since: mostly being silent, screaming when I burn my toast, and beeping every two years or so when its batteries run out. Recently however it began beeping for no reason, and I couldn’t get it to stop other than by removing the batteries. So I bought a new one and decided to tear down the old one.
![](https://www.tinytransistors.net/wp-content/uploads/2022/05/Smoke-detector-top-1024x766.jpg)