The notion that a tin foil hat can significantly reduce the intensity of incident radio frequency radiation on the wearer's brain has some scientific validity, as the effect of strong radio waves has been documented for quite some time.^[2] A well constructed tin foil enclosure would approximate a Faraday cage, reducing the amount of (typically harmless) radiofrequency electromagnetic radiation inside. A common high school physics demonstration involves placing an AM radio on tin foil, and then covering the radio with a metal bucket. This leads to a noticeable reduction in signal strength. The efficiency of such an enclosure in blocking such radiation depends on the thickness of the tin foil, as dictated by the skin depth, the distance the radiation can propagate in a particular non-ideal conductor. For half-millimeter-thick tin foil, radiation above about 20 kHz (i.e., including both AM and FM bands) would be partially blocked, although tin foil is not sold in this thickness, and numerous layers of tin foil would be required to sustain this effect.^[3]

The effectiveness of the tin foil hat as electromagnetic shielding for stopping radio waves is greatly reduced by the fact that it is not a complete enclosure. Placing an AM radio under a metal bucket without a conductive layer underneath demonstrates the relative ineffectiveness of such a setup. Indeed, because the effect of an ungrounded Faraday cage is to partially reflect the incident radiation, a radio wave that is incident on the inner surface of the hat (i.e., coming from underneath the hat-wearer) would be reflected and partially 'focused' towards the user's brain. While tin foil hats may have originated in some understanding of the Faraday cage effect, the use of such a hat to attenuate radio waves belongs properly to the realm of pseudoscience.

A study by graduate students at MIT determined that a tin foil hat could either amplify or attenuate incoming radiation depending on frequency; the effect was observed to be roughly independent of the relative placement of the wearer and radiation source.^[4] At GHz wavelengths, the skin depth is less than the thickness of even the thinnest foil.^{[citation needed]}

Tin foil hats are seen by some as a protective measure against the effects of electromagnetic radiation (EMR). Despite some allegations that EMR exposure has negative health consequences,^[5] at this time, no link has been verifiably proven between the radio-frequency EMR that tin foil hats are meant to protect against and subsequent ill health.^[6]

Electromagnetic hearing

Humans are able to detect modulated radio-frequency electromagnetic signals in the microwave range, hearing them as sounds. The perceived source of induced sound is located inside of or directly behind the head of the recipient, regardless of the location of the transmitter. The effect is believed to be caused by thermoelastic expansion of the brain exposed to microwaves.^[7]

During the Cold War, electromagnetic hearing was clinically studied in the United States for applications including covert message transmission and use as a non-lethal weapon. As a declassified National Ground Intelligence Center document points out:

It may be useful to provide a disruptive condition to a person not aware of the technology. Not only might it be disruptive to the sense of hearing, it could be psychologically devastating if one suddenly heard "voices within one's head".^[8]

A number of patents was granted by the United States Patent and Trademark Office for various applications of the technology, including "nervous system excitation", and "remotely monitoring and altering brain waves".

In 1962, Allan H. Frey discovered that reception of the induced sound can be blocked by a patch of wire mesh (not foil) placed above the temporal lobe.^[7]

 References

Mock Not...... you lot!!! When the alien invasion eventuates you people will be clamouring to be with us but Basil and I will just pass wind in your general direction........with our alfoil beanies on!!  It will be too late!!  Space Captain Basil Faultless and the  Masked Avenger also know as Fearless Duck, will be safe!!!

Ibbo............I never knew that you life was so fun filled!  Here was me feeling sorry for you, but all this time you have been faking your way around? 

Rafia Mats??   Come on mate.........wouldn't alfoil beanies have been better?? At least you would have been safe.

Don't knock the transistor radio in the bucket either........the only difficult part is changing the batteries.


"Using his own funds, Menkin has made and sent thought screen helmets to people all over the world for eight years"

Obviously this Menkin fellow is a man after your own heart Basil as he, like yourself, is self funded in his attempt to make the simple lives of the rest of us better, safer and  richer.

I for one............applaud you!!

Cruising Granny wrote:

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Jeez Basil, you most certainly have far too much time on your hands and head.
That's all very well, but who's the gherkin in the hat?
You in another life perhaps Basil?
And Ducky, you're just as bad, without the gherkin.

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