17 Feb 2005
2: Media Laboratory, MIT.
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On the Effectiveness of Aluminium Foil Helmets:
An Empirical Study
Abstract
Among a fringe community of paranoids, aluminum helmets serve
as the protective measure of choice against invasive radio signals. We
investigate the efficacy of three aluminum helmet designs on a sample group of
four individuals. Using a $250,000 network analyser, we find that although on
average all helmets attenuate invasive radio frequencies in either directions
(either emanating from an outside source, or emanating from the cranium of the
subject), certain frequencies are in fact greatly amplified. These amplified
frequencies coincide with radio bands reserved for government use according to
the Federal Communication Commission (FCC). Statistical evidence suggests the
use of helmets may in fact enhance the government's invasive abilities. We
speculate that the government may in fact have started the helmet craze for this
reason.
Introduction
It has long been suspected that the government has been using
satellites to read and control the minds of certain citizens. The use of
aluminum helmets has been a common guerrilla tactic against the government's
invasive tactics
[1]. Surprisingly, these
helmets can in fact help the government spy on citizens by amplifying
certain key frequency ranges reserved for government use. In addition, none of
the three helmets we analyzed provided significant attenuation to most frequency
bands.
We describe our experimental setup, report our results, and
conclude with a few design guidelines for constructing more effective helmets.
Experimental Setup
The three helmet types tested
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The Classical
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The Fez
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The Centurion
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We evaluated the performance of three different helmet
designs, commonly referred to as the Classical, the Fez, and the Centurion.
These designs are portrayed in Figure 1. The helmets were made of Reynolds
aluminium foil. As per best practices, all three designs were constructed with
the double layering technique described elsewhere
[2].
A radio-frequency test signal sweeping the ranges from 10 Khz
to 3 Ghz was generated using an omnidirectional antenna attached to the Agilent
8714ET's signal generator.
The experimental apparatus, including a data
recording laptop,
a $250,000 network analyser, and antennae. |
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A network analyser (Agilent 8714ET) and a directional antenna
measured and plotted the signals.
See Figure 2.
See Figure 2.
Because of the cost of the equipment (about $250,000), and the limited time for which we had access to these devices, the subjects and experimenters performed a few dry runs before the actual experiment
(see Figure 3).
Test subjects during a dry run. |
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The receiver antenna was placed at various places on the
cranium of 4 different subjects: the frontal, occipital and parietal lobes. Once
with the helmet off and once with the helmet on. The network analyzer plotted
the attenuation betwen the signals in these two settings at different
frequencies, from 10Khz to 3 Ghz. Figure 4 shows a typical plot of the
attenuation at different frequencies.
A typical attenuation trace form the network analyser |
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Results
For all helmets, we noticed a 30 db amplification at 2.6 Ghz
and a 20 db amplification at 1.2 Ghz, regardless of the position of the antenna
on the cranium. In addition, all helmets exhibited a marked 20 db attenuation at
around 1.5 Ghz, with no significant attenuation beyond 10 db anywhere else.
Conclusion
The helmets amplify frequency bands that coincide with those
allocated to the US government between 1.2 Ghz and 1.4 Ghz. According to the
FCC, These bands are supposedly reserved for ''radio location'' (ie, GPS), and
other communications with satellites (see, for example,
[3]). The 2.6 Ghz band
coincides with mobile phone technology. Though not affiliated by government,
these bands are at the hands of multinational corporations.
It requires no stretch of the imagination to conclude that
the current helmet craze is likely to have been propagated by the Government,
possibly with the involvement of the FCC. We hope this report will encourage the
paranoid community to develop improved helmet designs to avoid falling prey to
these shortcomings.
Acknowledgments
The authors would like to thank Andy (Xu) Sun of the MIT
Media Lab for helping with the equipment, Professor George Sergiadis for lending
us the antennae, and Professor Neil Gershenfeld for allowing us the use of his
lab equipment. (Please direct any queries to the authors, NOT these folks)