Swans on Tea

NASA SDO – The Venus Transit

The Mechanics and Meaning of That Ol’ Dial-Up Modem Sound

Of all the noises that my children will not understand, the one that is nearest to my heart is not from a song or a television show or a jingle. It’s the sound of a modem connecting with another modem across the repurposed telephone infrastructure. It was the noise of being part of the beginning of the Internet.
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This is a choreographed sequence that allowed these digital devices to piggyback on an analog telephone network. “A phone line carries only the small range of frequencies in which most human conversation takes place: about 300 to 3,300 hertz,” Glenn Fleishman explained in the Times back in 1998. “The modem works within these limits in creating sound waves to carry data across phone lines.” What you’re hearing is the way 20th century technology tunneled through a 19th century network; what you’re hearing is how a network designed to send the noises made by your muscles as they pushed around air came to transmit anything, or the almost-anything that can be coded in 0s and 1s.