So I accidentally popped the fuse in my C64, and had to order a batch of new ones. I'm also waiting for a couple of 32MHz ATXmega128's for you-know-what. Which leaves me without a project at the moment... unheard of!
Time to look around for parts. Solar panel, thermistor, low-power microcontroller and a RF module. Are you thinking what I'm thinking?
Project box, solar panel (9v/500mA max) and an AA battery for size comparison.
A wireless, out-door temperature sensor. Let's see if I can find the time to get this up and running before the new stuff arrives.
The two solar panels are rated max 9v/250mA each, but they are connected in parallel to double the amperage. To have this thing running 24/7 (even when dark outside) the micro controller will be at sleep most of the time, consuming about 1-2 µA. To save as much power as possible, the micro controller will activate components on demand via NPN transistors (RF module, voltage divider). The batteries will naturally be surge protected as well.
Now that was the thought. Let's see if there's time.