In this project you’ll take two simple ideas — a classic “cricket” noisemaker and a solar battery charger — and combine them into something great. Along the way you’ll also learn how to use the Arduino microcontroller as efficiently as possible for minimal power consumption.

Solar panels create electricity, of course — we’ll take that raw power and add a battery charging circuit to top up a 9V NiMH battery that powers the Arduino. But you can also use solar panels to detect ambient light — so in this project we’ll also use them as sensors to trigger the Arduino to perform a task when it detects that night has fallen.

What task? Making cricket noises! Your Solar Cricket will draw its power from the sun during the day and then use it at night to do its stuff. It’s fun for your garden, or for pranks — the circuit can be hidden away and used to drive someone crazy looking for the source of the sound!

To complete this project you should be comfortable using a soldering iron, following a simple schematic, and programming an Arduino board.

wp08_solar-cricket