The module has an (blue box). This adjusts the reference voltage for the LM393 comparator.
The (also known as the AMS1117-3.3 Adapter) is a power regulator module specifically designed to simplify the connection of nRF24L01+ wireless transceivers to microcontrollers like Arduino. Core Purpose yl-105 datasheet
The YL-105 is widely used in various industrial and commercial applications, including: The module has an (blue box)
Place the sensor 5mm above a white surface. Turn the potentiometer until the onboard LED just turns off. Now, the module will trigger reliably when seeing white vs. black. yl-105 datasheet
High-efficiency AMS1117-3.3 regulator ensures the wireless module receives stable power. Filtering Capacitors: