The Arduino connects to the FM radio module over I2C. The existing antenna was connected to the TEA5767 module. The radio module outputs stereo audio, but [Marcus] was content with using just a ...

Building an Arduino speed detector using IR technology to measure the speed of a moving object is much more cost-effective, and it is also very simple to build. All you need are a few basic parts, ...

You can, of course, buy I2C ADC chips and modules, but when you’ve already got a microcontroller that has ADC peripherals on board, why bother? [Pawel] wired up a tremendously simple circuit ...