Arduino Mega 2560 HC-05: Route Serial to Uno and PC
Build an Arduino Mega 2560 serial router with an HC-05 so your PC and phone can control an Uno over multiple UARTs...
RP2040-Zero MPU6050: Build a USB HID Air Mouse
Build an RP2040-Zero USB HID mouse with five buttons, then add an MPU6050 for tilt-based cursor control for a simple air mouse...
Arduino Uno DHT11: SD Data Logger with Timestamps
Build an Arduino Uno DHT11 data logger that writes timestamped temperature and humidity readings to a micro SD card using a DS3231...
Arduino S8050 Transistor: Switch Motors and LED Strips
Build an Arduino Uno S8050 transistor switch to control a 12 V LED strip and PWM a DC motor safely, including base...
Arduino Electromagnet: Relay and MOSFET PWM Control
Build an Arduino Uno 12 V electromagnet controller with relay or IRF520 MOSFET PWM, plus flyback diode safety, power-saving hold, and soft...
D1 Mini HX711 Load Cells: Wi-Fi MQTT Scale Build
Build a D1 Mini smart bathroom scale with four half-bridge load cells and an HX711, display weight on an OLED, and publish...
Arduino Nano W5500: Ethernet Web Server with JSON API
Build an Arduino Nano + W5500 wired Ethernet web server that shows DHT11 readings, switches a relay, and exposes a JSON API...
ESP32 HLK-LD2450: Live Web Radar People Tracking
Build an ESP32 + HLK-LD2450 mmWave radar web page that tracks up to three people with live X/Y coordinates, distance, and speed,...
ESP32 Telegram Bot: Remote Relay Pump Control
Build an ESP32 Telegram bot to switch a relay-driven pump with /on, /off, timers, and status replies, plus a local button override...
Arduino Nano WS2812 Matrix: Play Tetris on 8x8
Build Tetris on an Arduino Nano with a WS2812 8x8 LED matrix, three buttons, and a buzzer for a compact, playable LED...
Arduino Nano OLED: Triggered Waveforms to ~30 kHz
Build an Arduino Nano plus SSD1306 OLED mini oscilloscope with triggered trace, Vpp and frequency readout up to about 30 kHz using...
Arduino Nano LM339: Measure Inductance on OLED
Build an Arduino Nano LC ring meter using an LM339 and SSD1306 OLED to measure unknown inductors from about 5 uH to...