Digital oscilloscope is an indispensable tool for the design, manufacture and maintenance of electronic equipment. With the rapid development of technology and market demand, engineers need the best tools to quickly and accurately solve the measurement challenges. As the eyes of engineers, digital oscilloscope is very important to meet the current difficult measurement challenges. Because of the unique advantages of waveform trigger, storage, display, measurement, waveform data analysis and processing, digital oscilloscope is widely used. Due to the large performance difference between digital oscilloscope and analog oscilloscope, if used improperly, it will produce large measurement error, thus affecting the test task.