via https://www.youtube.com/watch?v=e0elNU0iOMY
Electrical Network Frequency analysis, ENF analysis, matches background hum against power grid logs. I talked to one of the researchers who works on it, and also set them a challenge. Thanks to @Answer in Progress, @Hannah Witton and @Steve Mould!
I’m at https://tomscott.com
on Twitter at https://twitter.com/tomscott
on Facebook at https://ift.tt/1WE18os
and on Instagram as tomscottgo