: The main advantage of this board is the onboard AMS1117 3.3V regulator, which allows you to power the wireless module using a 5V supply (e.g., from an Arduino's 5V pin) instead of the strict 3.3V required by the raw nRF24L01 chip.
The LM393 does not have built-in hysteresis, but many YL-105 modules add a small positive feedback resistor. Check your board; if not present, you may experience output jitter near the threshold. The datasheet often omits this, so add hysteresis in software (debouncing) or external resistors if needed. yl-105 datasheet
The designation typically refers to two common electronic components found in hobbyist and industrial circles: an nRF24L01 wireless module adapter board Go to product viewer dialog for this item. and a humidity/soil moisture sensor relay module . 1. YL-105 nRF24L01 Adapter Board : The main advantage of this board is the onboard AMS1117 3