23 Simple recording devices available from retail electronic stores allow the phracker to tape the discussions. The harnessing of the radio spectrum for wireless mass communications evolved from cordless telephones to paging systems and cellular telephones. The analog 26 signal is transmitted from the base unit through the telephone network like a regular call. The technology of a cordless telephone parallels that of a standard AM or FM radio. In fact, the radio signals transmitted between the handset and the base unit can be intercepted by ordinary AM radios, as well as other cordless phones, baby monitors, and other devices.
Cellular telephones operate similarly, but use a different portion of the radio spectrum.