Random Thoughts From Marybeth

Geek Humor

On the Effectiveness of Aluminium Foil Helmets: An Empirical Study

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.

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.

A network analyser (Agilent 8714ET) and a directional antenna measured and plotted the signals.

...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.

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.