Here’s the demo for the MIT App Inventor Oven thermometer I made.
You’ll need some flavor of Adruino, a Bluetooth SPP module, a max6675 thermocouple amplifier and a thermocouple to actually make the demo work.
I like these small 328 based boards and since they don’t have USB hardware it’s really easy to connect up the Bluetooth module. The ribbon cable is going over to a USB-ISP programmer.
The code updates every 400 ms but it could go a lot faster. I just don’t think its necessary.
Here’s a quick movie with a small butane torch being used to heat the thermocouple.
The code can be found here: