An Arduino-based DIY digital oscilloscope uses an Arduino board, an OLED display, and push buttons. The Arduino samples analog signals via its ADC, converts them to digital data, and processes this data to display waveforms on the OLED screen. Push buttons allow users to adjust parameters such as time base and voltage scale. The compact design makes it portable, ideal for basic signal analysis and educational purposes. This simple oscilloscope is perfect for hobbyists looking to explore electronics and signal processing.