Consumer Information On Wireless Phones - palmOne Vision Smart Device Treo 650 User Manual

Consumer Information on Wireless Phones

(The following information comes from a consumer information Website jointly sponsored by the
U.S. Food and Drug Administration (FDA) and the Federal Communications Commission (FCC),
entitled "Cell Phone Facts: Consumer Information on Wireless Phones." The information reproduced
herein is dated July 29, 2003. For further updates, please visit the Website: http://www.fda.gov/
cellphones/qa.html.)
What is radiofrequency energy (RF)?
Radiofrequency (RF) energy is another name for radio waves. It is one form of electromagnetic
energy that makes up the electromagnetic spectrum. Some of the other forms of energy in the
electromagnetic spectrum are gamma rays, x-rays and light. Electromagnetic energy (or
electromagnetic radiation) consists of waves of electric and magnetic energy moving together
(radiating) through space. The area where these waves are found is called an electromagnetic
field.
Radio waves are created due to the movement of electrical charges in antennas. As they are
created, these waves radiate away from the antenna. All electromagnetic waves travel at the
speed of light. The major differences between the different types of waves are the distances
covered by one cycle of the wave and the number of waves that pass a certain point during a set
time period. The wavelength is the distance covered by one cycle of a wave. The frequency is
the number of waves passing a given point in one second. For any electromagnetic wave, the
wavelength multiplied by the frequency equals the speed of light. The frequency of an RF signal
is usually expressed in units called hertz (Hz). One Hz equals one wave per second. One
kilohertz (kHz) equals one thousand waves per second, one megahertz (MHz) equals one million
waves per second, and one gigahertz (GHz) equals one billion waves per second.
RF energy includes waves with frequencies ranging from about 3000 waves per second (3 kHz)
to 300 billion waves per second (300 GHz). Microwaves are a subset of radio waves that have
frequencies ranging from around 300 million waves per second (300 MHz) to three billion waves
per second (3 GHz).
274 Safety