[Carlos] sent us his project that uses an Arduino as a pH meter. In order to sense the acidity or alkalinity of a solution, a glass electrode is connected to the ADC of the Arduino through a fairly complicated calibration, amplification, and filtering circuit. Admittedly, it may not be cheaper or as accurate as some commercial models, but it is an open project and can be interfaced with a computer via USB.
We saw this nifty little toy today and thought you guys might get a kick out of it. Its called the Hangmanduino, and as you can probably tell from the name, it plays hang man. This was an exercise in simplicity, you’ll notice there is only a single control for the entire game. We thought that the design was pretty cool, especially the single control. We weren’t surprised to see that this is actually the very same control we featured previously. You can download the code yourself from his website, if you want to make one of your own.
We’ve covered this sort of thing before, but there is something to be said for the simplicity of this tiny GSM alarm system by [trax]. The alarm system is designed to send the owner a text message when a sensor is triggered. This alarm only works with Siemens phones, but it shouldn’t be too hard to find one. The alarm is configured via a dip switch on the board and can also be armed and disarmed by text. The brains of this system is a PIC16F84A. The code and schematics are included at the bottom of the page.
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