The analogue input pins on your Arduino boards can be used to measure voltages from all sorts of sensors, and with a little extra circuitry and the method demonstrated by Warwick Smith it can be used to measure voltages up to 50 V. To make this possible the input voltages are broken down with two resistor voltage divider circuit, and the resulting readings modified in the sketch to return to the original voltage. It's an interesting example of analogue electronics and an Arduino - as explained in the following video:
For the tutorial, visit Warwick's website. And for more, we're on twitter and Google+, so follow us for news and product updates as well.
If you're new to Arduino and want to have some fun like the lads above, the first step is a solid board for your projects - our Freetronics Eleven - the Arduino-Uno compatible with low-profile USB socket, onboard prototyping space and easy to view LEDs:
