Arduino AC Grid Analyser

A fully fledged spectrum analyser on a basic Arduino board? In this article we'll show you how this is possible when the software is tailored to the available processing power. A standard Arduino can be turned into an AC line (‘mains’) supply spectrum analyser with the addition of a filter shield and a display shield. It uses a Fast Fourier Transform to visualise the 'pollution' on the AC grid supply at home or at the office.