We now live in an era where complex electronics can be dwarfed by their power supply. This is illustrated, in this case, by an WiFi-enabled ESP8285 chip which has been mounted on a tiny printed circuit board. It is designed to be connected and mounted to a 9-volt battery.
The board is set up to monitor environmental conditions including temperature, pressure, humidity, and ambient light. According to creator Pesky Products (which sells other interesting gadgets on Tindie as well) they can be conveniently placed on top of door thresholds to monitor conditions in a room.
Making this board even more interesting is that it has several general purpose input output (GPIO) pins that you can use to expand its sensing capabilities, or perhaps even add output functionality.
Although an incredible board, one thing that might limit some uses is the fact that it only lasts around 60 hours while powered by 9-volt battery. Possibly offsetting this, however, is the fact that it can go into “deep sleep” mode, saving power for when you really need it. The board’s creator is still experimenting with power-saving strategies; perhaps this time limit can be pushed out significantly in the future!
