On Saturday, we found a cool article where pinball machine display wheels were being used as a display. In that article, one of the listed inspirations was this giant Gottlieb wheel being used to display the water temperature of a pool. Before we go further, we’d like to mention that this project is hosted on a magazine’s website that requires you to register to get 1 free download. We did, and no financial information was required.
[Ludovic], they author of the project, was looking for an efficient and highly visible way to display the temperature in his pool. He wanted something he could see from 30 yards away, that had minimal power usage. These pinball reels were perfect, being easy to read and having virtually zero power draw when not updating.
Keep reading for a video and some more information.
The brains inside this project are an ATTin2313. The whole thing is powered up every 20 minutes to check the temperature. If the temperature has not changed, it powers back down. If it has, it updates the display. A 1farad capacitor is enough to keep the ATTiny alive between jobs so it can run the process again.
The downloadable PDF goes into extreme depth, explaining the theory, construction and running of the project and includes the full schematic as well as some helpful resources.