I have built a circuit that takes the reflection of a red dot laser and outputs 5vdc when the beam is broken. The problem I am running into is when more than one sensor is linked together. I start getting voltage to build up on the sensor output. The link below will show how the circuit is designed. I am not sure where the problems are but the circuit will work individually.
What do you mean with voltage build up? Where does increased voltage occur? Between which points?
Also, you experience a problem when you have multiple of these circuits connected together. Wouldn’t it then be better to explain how these are connected together? Do these share the same powersource/battery? Make a schematic of the combined circuit also.