Temperature Controller

This project rolls all the tools up into one part. I used the engraver to cut a PCB board, laid it out with Eagle PCB (there's an intuitive piece of software), the white parts were done on the 3D printer, and the system itself runs on an Arduino Mega V3. And a hot glue grommet :)

I cut a stack PCB board to plug on top of the the Mega, and that's where the keyboard, OLED screen, buzzer and buttons hook up.

This gizmo allows me to hook up an NTC Thermistor to the box and program two pair of high and low setpoints. One set of setpoints will sound an alarm, the other set will turn a relay on of off, controlling an AC line.

The whole thing runs on a 9V battery... I don't know what I was thinking. I have a box of 5V/12V power supplies, I could've just pulled the AC into one of those, and converted it over for power to the circuit. Oh well, that one is for Rev 2...

What would you use this for? Keeping water at a certain temp, sounding an alarm when something gets too hot or cold? I'm sure I will find something to do with it...