3 ms·
Amplitude Modulation, or AM, works by modulating the sound on the "peaks and valleys" of the frequency. If you were to look at the waveform of the carrier frequ
by connorlee 11y ago
Amplitude Modulation, or AM, works by modulating the sound on the "peaks and valleys" of the frequency. If you were to look at the waveform of the carrier frequency, you would see it as variance in the "power levels" of the signal, going higher and lower depending on what's being sent.
Because of how AM works, you can actually hear what's being transmitted by causing an electrical arc. It's the same concept of hearing a "buzz" from high voltage power lines, except in a controlled fashion to produce sound.
- Already__Taken 11y agoSo could you tune into the singing tesla coils with an AM radio is that the same idea?
- pdkl95 11y agoYou probably could, though I suspect you might need to re-tune between notes. If you have an old CRT, you might be able to achieve a similar effect with Tempest for Eliza[1]. [1] http://www.erikyyy.de/tempest/ http://www.erikyyy.de/tempest/
- jackhack 11y agoIndeed. One of the more interesting projects I've seen uses a tesla coil discharge as a guitar amp: https://www.youtube.com/watch?v=glrPioGqu3s https://www.youtube.com/watch?v=glrPioGqu3s A search for "singing Tesla coil" will turn up many more.
- xhrpost 11y agoCame here to ask this very question. Thank you. I take it then that a signal using frequency modulation or phase modulation (is that done anywhere?) wouldn't work then? Also, probably the same reason a ground loop in a home entertainment system will pick-up local AM stations. Edit: also, why does this work with the given RF frequencies which for AM are still much higher than audible sound frequencies?
- LesZedCB 11y agoElectroBOOM has a cool video[1] on youtube talking about some of that! His videos are some of my favorite. [1] https://www.youtube.com/watch?v=L5E4NiP4hpM https://www.youtube.com/watch?v=L5E4NiP4hpM
- gus_massa 11y agoThis video I very interesting. You should submit it.
- JoeAltmaier 11y agoThe carrier frequency is way above the hearing range. So it has to be shifted to the audible range. That happens by clipping and filtering. The arcing must be doing that somehow. Probably clipping; the low-pass filtering is done by the air/your ear.
- malexw 11y agoMy guess is that the arc through air gap is functioning as both the detector and speaker here. I suspect that the arc can only be sustained in one direction, probably from ground to the cable, which would give us the required clipping. At the same time, I assume the arc is acting as a plasma speaker, and, as you say, the air and our ear provides the low-pass filtering.