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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

#11

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

I don't think I'd want even minor RF burns - nasty nasty stuff.

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

#12

Wow, can anyone explain this?

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 structure ...

There used to be stories, not entirely urban legend, of people who lived close to AM towers hearing the station in the wiring of their home, or in their dental appliances. Not impossible, considering that many AM stations broadcast with 50kW of power (like the one in this video) and can be received across a large swath of the country.

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

#14

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

I don't think I'd want even minor RF burns - nasty nasty stuff.

What makes it worse than just a burn or a burn due to an electrical shock?

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

#15
post #14

Earlier quoted context omitted.

I don't think I'd want even minor RF burns - nasty nasty stuff.

What makes it worse than just a burn or a burn due to an electrical shock?

I can't find the reference but a ham operator once told me they can be imperceptible while they're happening.

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

#17

Wow, can anyone explain this?

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…

There used to be stories, not entirely urban legend, of people who lived close to AM towers hearing the station in the wiring of their home, or in their dental appliances.

Reminds me of a Gilligan's Island episode, Hi Fi Gilligan: https://www.youtube.com/watch?v=3x1XHv0sxro

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

#18

Wow, can anyone explain this?

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

Or, on a larger scale, a Zeusaphone/Thoremin: https://www.youtube.com/watch?v=3ff_AXVlo9U

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

#20
post #14

Earlier quoted context omitted.

I don't think I'd want even minor RF burns - nasty nasty stuff.

What makes it worse than just a burn or a burn due to an electrical shock?

Normal burns are usually localized to the surface of your skin. RF burns conduct all the way through your tissue, heating from the inside. It's a much deeper, more painful burn that takes an abnormally long time to heal.

(Or so I'm told. So far I've been able to avoid experiencing one myself.)

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