Quoted from Reznnate:
I'm having a problem with the bowling alley opto that detects bowling pin hits. Every shot is a miss.
I've swapped the optos (just in case) and confirmed the optos are getting power, but still don't see switch messages when I move my hand in front of the windows. The optos are aligned with the holes in the alley.
Any other thoughts on how I might fix or debug this?
Check the plug end - connectors. Push wires into connector with flat blade screw driver - make sure wires are seated.
Not sure if the sender and receiver are on wrong sides? Just a guess not sure it matters?
Maybe post a picture so we can compare to our machines.