Welcome to the next installment of "Dabbling in Electronics"! Over the spring and summer of 2020, I helped a non-profit develop an open-source, non-contact infrared (IR) thermometer, the kind you point at someone's forehead and press a button or pull a trigger to take a temperature. They believed at the time that due to the COVID-19 pandemic there would become a shortage of commercial units of these thermometers for screening people for fever at businesses and non-profits. I submitted a proposal to the initial design competition, but it wasn't selected for further development.
Mostly for the fun of learning new things, but also to validate my design choices, I decided to build a prototype of my proposed design mostly on my own. This article is the first part in a series about developing that prototype from scratch and what I learned by doing so. I will be writing this series as I progress step-by-step toward having a completed thermometer including custom printed circuit board (PCB) and 3D-printable handheld device enclosure. Right now, I will just describe the basics of the thermometer and some key design choices.
