Mark, Start with:
https://en.wikipedia.org/wiki/Electrical_network_frequency_analysis and then spend some time searching. There's hundreds of technical papers and interesting details. Definitely time nut material. /tvb ----- Original Message ----- From: "Mark Sims" <[email protected]> To: <[email protected]> Sent: Wednesday, April 06, 2016 10:27 PM Subject: [time-nuts] Building a mains frequency monitor > And that can be very interesting... a while back I read some stories on how > the NSA, police, etc could find out where an audio recording was made by > correlating AC hum in the recording with logs that they had of the power > grids. Apparently logging AC mains is rather popular among the spooky / law > enforcement types around the world (Britain appears to be rather fond of it). > I did an experiment where I logged the AC mains at a few places around town > along with some audio recordings made in the same areas. I used some simple > correlation software and could easily determine where and when the recordings > were made. > ----------------- >> Phase noise? The line frequency shifts phase every time a major > electrical load is added or dropped from the power line. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
