If you have a drawer full of sensors, chances are you have a few green modules labeled MH Sensor Series "Flying Fish" . These are arguably the most common infrared (IR) proximity sensors on the market. They are cheap, reliable for line-following robots and tachometers, and they run on 5V.
You don't need a "fixed" datasheet; you just needed the correct one. The MH Flying Fish is a TCRT5000 reflective sensor paired with an LM393 comparator. Treat it as a digital switch that triggers when something gets within 2cm. Mh Sensor Series Flying Fish Ir Sensor Datasheet Fixed
Your potentiometer is mis-set. Turn the blue box trimmer counter-clockwise. The Flying Fish has a digital output, not analog. The pot adjusts the threshold . If the threshold is too low, it will always read "1" (nothing detected). If you have a drawer full of sensors,