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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

#61
post #42

Earlier quoted context omitted.

> What 50 kilowatts of RF power sounds like through a jumper cable And you still got it wrong.

What's wrong with it?

Maybe he thinks it should be 'kiloWatts'. CamelCase impairment?

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

#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.

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

#64
post #58

Earlier quoted context omitted.

The bird would be dead. RF power will happily fry tissue if you get close enough to the radiator.

Excuse my ignorance, but wouldn't the bird need to be grounded for the power to jump? Or does that only apply to electrical circuits?

[deleted]

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

#65
post #27

Earlier quoted context omitted.

I think that usage is OK. It's like saying "40W of light". In this case, it tells us there's some RF energy and also that it's RF energy of the "50 kW" type.

I think "40 W of light" is a great example of why this imprecise, or quite frankly, incorrect usage is troublesome. 40 W of old timey lightbulb light is useful if you want to sit close and read a book in the evening, whereas 40 W of a modern LED bulb light is a great thing to have if you want to fend of a pack of marauding undead.

This may be slightly off topic, but look at this cool LED[0]! It's a 150W 18000lumen LED, which is the raddest thing ever.

[0][http://www.cree.com/LED-Components-and-Modules/Products/XLam...]

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

#66
post #49

Earlier quoted context omitted.

The voltage applied to the cable is directly proportional to the audio signal, overlaid on a ~1 MHz carrier. All you need is a mechanism that transforms those voltages into vibrations or pressure waves. Presumably, since it seems to happen only when he's striking an arc, it's related to the local heating of the air in the gap ... But I guess it could be electromagnetically induced vibrations of the cable or the tower…

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…

That happened to me sometimes, living in the UK --- my computer speakers would come on in the middle of the night and start whispering to me in French. It was exactly as creepy as it sounds.

I think I did eventually pin down which station they were picking up, but I've forgotten now. Interestingly, since I've moved to Switzerland, it's stopped. Maybe the signals don't get through Swiss customs.

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

#68
post #49

Earlier quoted context omitted.

The voltage applied to the cable is directly proportional to the audio signal, overlaid on a ~1 MHz carrier. All you need is a mechanism that transforms those voltages into vibrations or pressure waves. Presumably, since it seems to happen only when he's striking an arc, it's related to the local heating of the air in the gap ... But I guess it could be electromagnetically induced vibrations of the cable or the tower…

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.

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

#69

Wow, can anyone explain this?

Same way as a plasma speaker https://www.youtube.com/watch?v=PJpn2PzhvP4

It would be cool to see a guitar amplifier that worked like this. It seems dangerous, but that would be awesome to hear/watch.

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

#70

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.

You probably can't because, if nothing else, the water should act like a faraday cage.
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