I am trying to help daughter with school proj and have built kit so works as designed. have etra kit and wondering how to make it so that buzzer starts on and breaking beam turns it off?
Swap pin 9 and 10 of LM324
I am trying to help daughter with school proj and have built kit so works as designed. have etra kit and wondering how to make it so that buzzer starts on and breaking beam turns it off?
Swap pin 9 and 10 of LM324