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Electromagnetic Disturbance at Sound Bandwidth

04/26/2017 3:25 AM

Would EMW interference or signal discharge or emiited at audible bandwidths literally produce sound?

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#1

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 3:39 AM

Of course it does. There is a transformer in a piece of equipment not a metre away that is producing audio at 50Hz and its harmonics.

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#2

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 3:43 AM

How could it not?

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#3
In reply to #2

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 8:33 AM

"How could it not?"
If there was nothing physical in which it could induce movement.... e.g. Try playing your hi-fi in a vacuum
Del

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#6
In reply to #3

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 9:52 AM

<...Try playing...hi-fi in a vacuum...> Is that where the music gets one spaced out?

Just askin' .

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#7
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Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 10:10 AM

At least no one can hear that guitar riff scream in space.

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#8
In reply to #7

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 10:15 AM

Thank goodness for small mercies.

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#4

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 9:16 AM

An audio frequency electromagnetic wave (EMW) will not produce a sound unless there is something that can be moved by the EMW and it moves air which stimulates the hearing receptors in the ear. Since many people do have bits of metal implanted in various parts of their body for functional and decorative purposes it is conceivable that one could hear an EMW produced sound that others cannot. A schizophrenic episode can also produce the same effect.

[They're laughing at you]

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#5

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 9:35 AM

The EM spectrum at audio frequencies is a cacophony - if you could hear it. Atmospheric noise (called 'spherics'), blasts of white noise from nearby (<1000 km) lightning discharges, descending tones (called 'whistlers') from distant lightning whose RF energy has passed through the magnetosphere, sounds like flocks of birds, very low-pitch constant tones called the Schumann resonances. And these are just the naturally-occurring ones. Add to that manmade ones like powerline hum and its harmonics, electrical noise from motors and light dimmers, and so forth. The bottom of the EM spectrum is a very, very noisy place. Do you hear any of it? No. Why not?

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#9
In reply to #5

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 10:17 AM

(1) some of the most active (noisy) parts of the low-frequency spectrum are below the audible range of frequency being below 20 Hz.

(2) there may well be nothing to couple E-M frequencies in that range into compression waves in the acoustic spectrum. All sounds that we can audibly hear are compression-rarefaction waves in the 20-20,00 Hz band.

(3) Elephants (and certain Republicans) can actually hear groanings too deep for normal human comprehension. This is how we communicate long range across the Savanna.

(4) Electric discharges in air are particularly efficient at producing (a) shock waves, and (b) broad spectrum compression and rarefaction waves, that show up as "noise" at long range.

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#11
In reply to #9

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 10:19 AM

My question was directed to GM to get him to think about the 'why'.

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#10
In reply to #5

Re: Electromagnetic Disturbance at Sound bandwidth

04/26/2017 10:17 AM

Because the listener has no decorative jewellery piercings? No? Aw go on. Do tell.

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#12

Re: Electromagnetic Disturbance at Sound Bandwidth

04/26/2017 1:22 PM

Where are my GAs you miserable shower?
Redfred gets 2 when I pointed it out first!!!! ... Ohhhhh I shall go and sulk in my secret cat nest.... grrrr ftzzz hisss
Del

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#13

Re: Electromagnetic Disturbance at Sound Bandwidth

04/26/2017 2:40 PM

A beam of microwaves can generate the sensation of sound inside your head, known as the Frey Effect.

https://en.wikipedia.org/wiki/Microwave_auditory_effect

https://en.wikipedia.org/wiki/Electrophonic_hearing

In this case, a tinfoil hat may just protect you!

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#14
In reply to #13

Re: Electromagnetic Disturbance at Sound Bandwidth

04/26/2017 3:01 PM

I wonder if this is due to the cilia or their attached nerve cell cooking to soft boil. Ouch!

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#15
In reply to #13

Re: Electromagnetic Disturbance at Sound Bandwidth

04/27/2017 11:19 AM

Yes, SE and Rixter, I am sure that sound is heard just prior to cranial explosion due to the excess cranial steam pressure. It might even be heard by others in the surroundings. I once suggested a weapon of warfare to the DoD that would utilize a satellite in stationary orbit (adjustable to the needed area), large solar arrays, and a 50 MW microwave beam collimated as a TEM00 maser. By raster scanning the areas where enemy combatant movements were taking place, the entire opposing force could be neutralized within a few minutes without escape.

I suspect it violates the Geneva convention on the so-called rules of war. Nevertheless, I estimate this would be a very formidable weapon if used on a conventional or an insurgent conflict.

The whole story about hearing microwaves, reminds me of a story told by a member of our research group at University of Utah once: While in the USAF, he was stationed at a far north NORAD radar base. He had racked out, locked out, and tagged out a dome for servicing, and was inside when some dumb az Lieutenant came in and saw the module pulled from its bay, and overcame the LOTO to plug it back into service! My buddy had to "outrun" the rotating mechanism (he would have been simultaneously crushed and fried to a crisp), and managed to jam the mechanism with the only tool to hand, a screwdriver. I think he actually clocked the officer, and got away without a courts martial.

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#16

Re: Electromagnetic Disturbance at Sound Bandwidth

04/27/2017 11:22 AM

You cannot hear audio-frequency RF directly, if that's what you're asking. You need some sort of RF-to-audio conversion mechanism.

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Andrew Westman (3); Del the cat (2); James Stewart (3); PWSlack (4); redfred (2); Rixter (1); Tornado (1)

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