Power Sensor

TLDR: I made a current sensor that reports over cellular network to the Internet, providing a summary webpage and email alerting for when the current dies.

The project box is open with one circuit board attached to each side. — The inside of the finished project.

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RasPi Flow Meter In A Pinch - Part 2

META: Part 1 describes the problem I’m trying to solve here. I need a way to monitor water flow through my water filter over several days, and I don’t want to sit and watch it. So - I took a Raspberry Pi I’ve got and a little Python and hacked a solution together. The basic idea was that I’d position a plastic cup below the output stream of the waste water, I’d put two wires into the cup, I’d put a voltage on one wire and attempt to see the voltage on the other.…

RasPi Flow Meter In A Pinch - Part 1

META: This first part is about the problem that caused me to build the solution. Part 2 is about the solution. My new place has an awesome feature that was disabled when I moved in - a reverse osmosis water filter! It’s not a whole-house hookup, it’s just for the refrigerator and a dedicated tap on the sink. We definitely wanted to use this thing! At first, I just turned it on and it seemed to work fine.…

LCD Modules

I’ve never built anything with an LCD on it before, but it seems like it’d be useful. Here’s some good info on creating an project with an LCD and an Arduino: http://arduino.cc/en/Reference/LiquidCrystal It’s a library of functions that make it very easy to work with the LCD controller. The controller has to be compatible with the HD44780 controller’s instruction set, but that’s basically an industry standard. Mouser has a selection of 20x4 character displays:…