Linux Doorbell (Raspberry A+)

youmagine

I got fed up with our doorbell - the very loud and heart-stopping shrill sound was really getting to me. So I started building one using an Arduino controller, but then I realized it would be a lot more fun to be able to change or install doorbell sounds via network on the doorbell itself, no SD card removal and plugging into the card reader and plugging back in - just SSH or FTP into your doorbell and upload a new sound file! When the new Raspberry Pi model A+ came out, it was set and I needed a nice enclosure for the electronics and the two loudspeakers. Printing the case isn't easy, but it's doable - I included my G-code file created with Simplify3D for my MakerGear M2 printer. I printed this with PLA and used a raft. The Raspberry Pi Model A+ is mounted on two slides (see included file) which fit into the enclosure. The doorbell button is connected to GPIO7 and is being read via event detect (interrupt) in Python. The loudspeakers are driven by a Stereo 3.7W Class D Audio Amplifier - MAX98306, which I bought here: http://www.exp-tech.de/Shields/Audio/Stereo-3-7W-Class-D-Audio-Amplifier-MAX98306.html The loudspeakers are 3" 4 Ohms 3Watt and have to be glued into the case: http://www.exp-tech.de/Zubehoer/Sonstige-101/Lautsprecher-3-Durchmesser-4-Ohm-3-Watt.html Usually in Germany, there is a little 8V/1A AC transformer in the electrical cabinet for the standard doorbell. I replaced it with a 5V/2.4A DC switching supply for DIN-Rail from Reichelt electronics: https://secure.reichelt.de/Schaltnetzteile-fuer-Hut-Schiene/MW-DR-15-5/3//index.html?ACTION=3&GROUPID=6539&ARTICLE=148095&SEARCH=MW%20DR-15-5&OFFSET=500&WKID=0