Embedded Lab

Here’s a DIY mailbox alert system that will free you from guessing, wondering, or making wasted trips to the mailbox only to find it empty. Yes, this Arduino-based mailbox notifier sends you a text whenever you get mail. The device uses a simple light-dependent resistor (LDR) to detect the light levels inside the mailbox. When somebody opens the mailbox, the light level goes up and Arduino knows it is time to send a text. It can also serve as a security device to avoid your mail being stolen if the mailbox is accessed during non-delivery hours. A push switch button at the front of the device is used to arm or activate the sensor. Once the sensor is activated, the next time the mailbox is opened, a text message is sent to your cell phone. It will not send any text again until it’s armed again. This ensures that you don’t get a text every time you open the mailbox. So, a good practice would be to arm the sensor system every time you go pick up your mail.