All, I could use some help. I would like to measure mains frequency in real-time and pass the data through a high-level programming language (preference of Python). I am not sure where to start with this project, I assume commercial mains frequency analyzer exist, however, my google searches have only found highly engineered units like this: http://www.arbiter.com/catalog/product/model-1133a-power-sentinel.php . Which I'm sure is a great piece of kit, but when you have to ask for the price you probably can't afford it. Has anyone solved this problem before, on a tight budget? Thanks in advance.