Can you buy a working radar module for $12? As it turns out, you can. But can you make it output useful information? According to [Mathieu], the answer is also yes, but only if you ignore the ...

This module features a vibration sensor, an adjustable trimpot, and a comparator chip to give an adjustable digital output based on the amount of vibration. The multiturn trimpot can be adjusted to ...

Out of curiosity, I bought a strain gauge sensor module after it appeared on sale. This write-up is fuzzy, since I decided to write based on a quick inspection of it. Have fun reading my little post ...