Listening radio with grass
Why Hacker News recommends it
HN commenters bring it out whenever AM radio, strong transmitters or accidental demodulation comes up, as the classic example of grass playing radio.
What it is
Two experimenters hold blades of grass near a radio transmitter antenna and hear the AM station through the arc between antenna and grass. It is a short, informal demonstration of unintentional AM demodulation.
Recommended by 0 HN commenters across 0 different months, 2017 to 2026.
What Hacker News said
Cites heywire · 2017-04 · on “MP3 for Image Compression (2006)”
Not exactly what you were asking for, but made me think of these: [LINK] and [LINK] and if you go down the rabbit hole, you end up here: [this video]
Cites userbinator · 2019-11 · on “Sweet Home Alabama Played on Tesla Coils (2012)”
I suspect it's accompanied by some speakers too, because otherwise the sound would be a lot "emptier" and less bassy. Similar device: [LINK] Also reminds me of this old video: [this video]
Cites gambiting · 2020-01 · on “WLW: America's 500,000 watt radio station (2015)”
Reminds me of this - [this video] Obviously don't do this. I would be concerned about standing this close as well, radio burns are super nasty.
Cites VBprogrammer · 2020-06 · on “My dad launched the quest to find alien intelligence”
Fair point. Call it 60w or even 1w if that feels better. It's still many orders of magnitude over what you would be receiving across space from another solar system. Also, for mild amusement, your comment reminded me of this video [this video]
Cites rcfox · 2022-09 · on “PC wakes from sleep when changing clothes”
AM radio is such a simple modulation scheme that even a piece of grass can be used to demodulate it, with enough power. [this video]
Cites gambiting · 2023-03 · on “Battery Free Gameboy”
Well, if you're mad enough and don't care about trivial things like life, you can listen to AM radio by just touching the mast with any random item: [this video]
Cites blincoln · 2023-08 · on “Radio frequency hearing in humans and its effects (2003)”
I grew up in a house that was next door to a radio rebroadcasting facility, and we could definitely hear the radio station coming from the walls of our house sometimes, e.g. even their station identification so there was no ambiguity. I assumed it was the house wiring (mostly knob and tube) acting as an antenna. I'm reasonably sure that was AM, though. Was the sound you heard like either of these? [LINK] [this video]
Cites bisby · 2023-09 · on “A scientific curiosity that happened to me”
Certainly a brass headboard doesn't have a semiconductor in it. But that doesn't mean the story is bullshit. Just that it's not working in the way they think it is. Heres an example of a thistle being used to convert an AM signal into audio. Granted, they are touching the plant directly to the broadcast tower, and it's outputting enough power that it starts burning and even burns the hand of the person holding the plant. [this video]