Refrigerator Door Alarm

Do your kids leave the door to the refrigerator open? Or does your celery reach out to keep the door from closing properly when you turn your back? Heres a simple circuit that beeps whenever the door is open for an extended period of time (which will also put a little pressure on the fridge loiterers in the house). Simple Refrigerator Door Alarm Circuit Diagram The photocell has a very high

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