Few pics of my very simple DTH22 sensor long range (used to monitoring my wine cave temperature). A simple case 3D printed...

I share today an experimental project for my mailbox. The idea was to get a pushover notification when mail delivery is done. I live in an apartment and hate to do a stupid walk to check downstairs my mailbox. Initial tests have been done with a weighter sensor on the bottom of the mailbox. But unfortunately it was too dependent on the position of the letters. During evaluation of the apds 9960 proximity sensor I got this simple idea to mesure the proximity from the bottom to the top of the mailbox, and when a letter is put inside the mailbox, the sensor detecte a change on the distance and send a notification. I don't have yet enough experience on the battery duration.