World's Smallest Radio Built; Still Plays Bad Music
And you thought the iPod was a breakthrough in terms of size and decibels. Well, just up the road from Apple, physicists at the University of California, Berkeley have built the smallest radio yet--a single carbon nanotube dubbed the Nanotuberadio that's one ten-thousandth the diameter of a human hair.
So what did these scientists want to hear the radio play? Derek & The Dominos' rendition of "Layla" and the Beach Boys' "Good Vibrations." Which goes to show that the good scientists know more about good science than good music. Not exactly Alexander Graham Bell's "Mr. Watson, come here I want you" but close enough.
The nanoradio, which is currently configured as a receiver but could work as a transmitter, is 100 billion times smaller than the first commercial radio, and could be used in applications such as cell phones and microscopic sensors, according to team leader and physics professor Alex Zettl.
Zettl, Kenneth Jensen, Jeff Weldon, and Henry Garcia came up with a way of building a single carbon nanotube that works as an all-in-one antenna, tuner, amplifier, and demodulator for both AM and FM. The nanoradio detects radio signals by vibrating thousands to millions of times per second in tune with the radio wave. In normal radios, ambient radio waves from different transmitting stations generate small currents at different frequencies in the antenna, while a tuner selects one of these frequencies to amplify. In the nanoradio, the nanotube, as the antenna, detects radio waves mechanically by vibrating at radio frequencies. The nanotube is placed in a vacuum and hooked to a battery, which covers its tip with negatively charged electrons, and the electric field of the radio wave pushes and pulls the tip thousands to millions of times per second.