It’s something [mircemk] demonstrates, with an Arduino-powered magnetic field strength meter that uses a UGN 3503U Hall effect device. The circuit is extremely simple, comprising the sensor, an ...

Using the SS49E linear Hall effect sensor in pairs on four sides of a square, the setup proves quite straightforward.

Would you believe it, the ESP32 popular Wi-Fi and Bluetooth chip has a built-in Hall effect sensor. Espressif Systems makes the chip, and its ESP32 data sheet has nearly no mention of the Hall sensor ...