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What 50,000 watts of RF energy sounds like through a jumper cable

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Re: What 50,000 watts of RF energy sounds like through a jumper cable

#81

Post by runarb »

50CNT wrote: post #60
derefr wrote: post #51

Earlier quoted context omitted.

You mean they conduct from the entry-point to ground, similar to a lightning strike or electrical burn? Or is this more like a radiation burn? Actually, now that I think about it, it'd actually be most similar to how a microwave heats meat, wouldn't it? Microwaves being within the RF part of the EM spectrum and all. (Though not quite the same, given the lack of dipole interaction with water molecules outside of the p…

That reminds me of an urban legend regarding microwaves, which doesn't seem entirely infeasible. It involves a man working at a small fast food stand, who worked next to his microwave. Now his microwave was used often, and it had a small hole in the metal screen allowing microwave radiation to leak out. The man slowly starts to feel abdominal pains after a while, goes to his doctor, who diagnoses it as liver problems…

There is also the story of Anatoli Bugorski. He was debugging the worlds most powerful particle accelerator when he managed to look into the beam: http://www.strangerdimensions.com/2014/01/13/anatoli-bugorsk...

Re: What 50,000 watts of RF energy sounds like through a jumper cable

#84

Post by batat »

tlrobinson wrote: post #9

Even better: some crazy Russian/Ukrainian kids listening to the local radio station through weeds (and occasionally getting some minor RF burns): https://www.youtube.com/watch?v=82s5Q3GIO9I

It's abandoned radio station in Brovary, Ukraine, I've been there several times. There were two antennas — 180 m and 270 m with 100 and 150 kwt transmitters (later up to 250 kwt). Until 1988 they were used for radio jamming (BBC, Voice of America, Deutsche Welle), later for radio broadcasting [1]

AFAIK you could get serious burns [2][3] even when antenna was not powered any more. In this case it works just like huge receiving antenna, getting kilowatts of RF energy directly from atmosphere. Before the thunderstorm ropes holding the antenna literally glowed due to corona discharge effect.

A few years ago both antennas were demolished [4][5]

[1] http://vk.cc/4LQeGa (wiki, Ukrainian)

[2] http://io.ua/20405915p

[3] http://io.ua/20405932p

[4] https://www.youtube.com/watch?v=j6NgzzFrCv4

[5] https://www.youtube.com/watch?v=Pn6sLpDS0Ks

Re: What 50,000 watts of RF energy sounds like through a jumper cable

#85

Post by gpvos »

rcxdude wrote: post #68
plorg wrote: post #49

Earlier quoted context omitted.

I have a friend who lives as close as one can legally live to a 100kW FM transmitter. He received a pair of very cheap speakers when he built a new computer but was unable to use them because if they were plugged in the radio signal would come right out of the speakers. It seemed that the signal path into the speakers was through the input wire (rather than, say, the power cable or the wires between the amplifier and…

A diode isn't actually required for AM reception, it just happens to be one of the better ways if doing it. In fact, any non-linearity in a circuit will act to demodulate AM signals, as the video and your friends experience nicely demonstrate.

He was talking about FM, not AM. Which makes it rather weird, as you actually need more of a circuit to decode it.

Re: What 50,000 watts of RF energy sounds like through a jumper cable

#86

Post by kuschku »

runarb wrote: post #81
50CNT wrote: post #60

Earlier quoted context omitted.

That reminds me of an urban legend regarding microwaves, which doesn't seem entirely infeasible. It involves a man working at a small fast food stand, who worked next to his microwave. Now his microwave was used often, and it had a small hole in the metal screen allowing microwave radiation to leak out. The man slowly starts to feel abdominal pains after a while, goes to his doctor, who diagnoses it as liver problems…

There is also the story of Anatoli Bugorski. He was debugging the worlds most powerful particle accelerator when he managed to look into the beam: http://www.strangerdimensions.com/2014/01/13/anatoli-bugorsk...

And he’s become part of popular culture due to the annual satirical year in review panel at the C3 congress giving out the fictional "Anatoli Bugorski Award for applied nuclear safety".

Re: What 50,000 watts of RF energy sounds like through a jumper cable

#89

Post by tombrossman »

nielsole wrote: post #63

I was once in a completely empty swimming pool (~25*10 m size) The surface of the pool was completely undisturbed. When I put my head under water I could hear a radio voice. Since I could not rule out the possibility that it was simply audio from nearby speakers that I simply could not hear through the air, I was always wondering whether it would be possible to listen to radio waves in water.

Underwater speakers exist (think synchronized swimming or a PA system at a public pool). The sound quality isn't super but voice quality is good. Is it possible the pool was equipped with one?
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