: Features a 3.8-inch monochrome LCD screen (1101G model) for real-time waveform display.
Find the main processor (U1 – often an STM32F103). In the schematic, verify that pin 14 is connected to a 8MHz crystal. Unverified copies often swap pin 13 and 14.
This article is for informational purposes. Always consult a qualified biomedical engineer for actual device repairs.