Have a lackluster datasheet for your sensor, but a demo app from the vendor that seems to calculate the value you need? If the app is written in .Net (Visual Basic or C#) -- and if it's Windows based, it probably is -- you might be able to decompile the app and find that magic formula you're looking for!
This project combines a whole heap of modules to enable a Raspberry Pi to power a large 1.2 inch 4 digit 7 segment display. A small switch switches the display between showing the temperature and the current time. The project uses a real-time clock (RTC) to ensure that the Pi always has the correct time, even if it is not connected to the Internet.
XBee modems are one of the easiest ways to create a wireless point-to-point or mesh network. They have error correction, are configured with AT commands, come in multiple flavors and can create a wireless serial link out of the box! I wanted to make a wireless Arduino project but all the adapter boards on the market made me unhappy. So I designed what I think is an excellent low-cost adapter board.
This tutorial by John De Cristofaro (johngineer) aims to teach you how to take photos of your hacks and projects for sharing on the web, and perhaps even in print. It focuses on smaller items, less than 6”x6”x6” in size. Bigger projects present their own unique problems that are beyond the scope of this article. However, you can always “scale up” the methods presented here to take pictures of larger subjects, at least to a point.
This is actually not any sort of product or public project (!) - its something I designed to help me evaluate solar panels and how they act when charging batteries. Normally this requires a lot of multimeters and its a bit of a pain to do if you have to constantly change out panels. So I decided I would build a specialized tool that would assist me.
Here is a quick project for an electronic Halloween pumpkin. With a bit of hacking a $1 plastic pumpkin is upgraded: a sensor embedded in the nose detects when people get close and will play scary sounds and animates LEDs on the face. The sounds are stored on an SD card so its easy to change and customize what the pumpkin says, while the code is written for an Arduino so it's easy to modify the behavior. I'm going to have this pumpkin outside my door to freak out the little kids who go to daycare nearby. Boo!