4 ms·
> this is the same country that has the national power grid introduce "hum" (or whatever it is technically callled) in the signal so that a time reference can b
by Twisol 4y ago
> this is the same country that has the national power grid introduce "hum" (or whatever it is technically callled) in the signal so that a time reference can be decoded from it.
I don't think that's intentionally introduced. My understanding was that mains hum in any grid is an artifact of a noisy signal that just happens to be useful as a forensics fingerprint.
https://en.wikipedia.org/wiki/Mains_hum https://en.wikipedia.org/wiki/Mains_hum
- dylan604 4y agoYes, it seems I crossed a few streams in my head. Here's an article[0] talking about how the forensics is done because someone is creating a database of all of the fluctuations that give it the forensic finger print rather than it being deliberately injected. [0]https://www.bbc.com/news/science-environment-20629671 https://www.bbc.com/news/science-environment-20629671
- ErikCorry 4y agoFascinating
- roywiggins 4y agoI believe that the frequency actually is deliberately managed... to keep old clocks synced. https://www.kccscientific.com/the-dirty-little-secret-about-mains-power-line-frequency/ https://www.kccscientific.com/the-dirty-little-secret-about-...