[Klaus] wanted some sort of aid for parking his car, and after running across a $4 ultrasonic sensor, decided to build his own speaking distance sensor (.de, Google Translation). Inside [Klaus]’ ...

Sometimes, it’s time to shut down the oscilloscope, and break out the cardboard and paints. If you’re wondering what for, well, here’s a reminder of an Instructable from [CrazyScience], that brings us ...

A low-cost (~$100), do-it-yourself (DIY) ultrasonic water level sensor/datalogger has been designed, constructed, and tested for use in education, citizen/community science, and research settings. The ...