This is an Arduino-based Proximity Sensor circuit wired using the popular HC-SR04 Ultrasonic ranging module,used here for non-contact object detection purpose. The HC-SR04 module includes ultrasonic ...
The world needs more blinky lights, and [Bertus Kruger] has created a neat way to make lights blink wirelessly. He has a footprint in the middle of the board for soldering the castellated ESP8266 ...