4 ms·
> As noted, the mains hum is a major source of havoc. Use batteries? Or whatever is the most stable way to generate direct current. Turning a dynamo maybe or i
by whoopdedo 11y ago
> As noted, the mains hum is a major source of havoc.
Use batteries? Or whatever is the most stable way to generate direct current. Turning a dynamo maybe or is that too simplistic?
- raverbashing 11y agoBatteries won't help. Because a person (to which the circuit is attached) is a very good antenna picking up the hum from the wires around. Filtering the 50Hz/60Hz from the power supply is relatively easy.
- moron4hire 11y agoNeeds a humbucker pickup! https://en.m.wikipedia.org/wiki/Humbucker https://en.m.wikipedia.org/wiki/Humbucker
- detaro 11y agoBatteries or very clean PSUs help, but you can pick up mains hum even if your measuring device is not connected to the power grid. Every cable and even the body your measuring on pick it up. Simple demonstration: hold an oscilloscope's probes in your hand and you'll clearly see 50/60 Hz showing up.
- M2Ys4U 11y agoInterestingly, this is used to geolocate multimedia recordings, as different places will have different mains interference. If you know roughly when a recording is taken and what the state of the power grid over the target area (country, region or state etc.) is, you can match the recording with its location - and vice versa. https://www.ece.umd.edu/~minwu/public_paper/Conf13/1305_ENFLocalize_icassp13.pdf https://www.ece.umd.edu/~minwu/public_paper/Conf13/1305_ENFL...