Private Audio
Before satellite, Muzak was transmitted to department stores on FM subcarriers. The United States Federal Communications Commission (FCC) also allowed betting parlors in New York state to get horse racing results from the state gaming commission via the same technology.
Many non-commercial educational FM stations in the US (especially public radio stations affiliated with NPR) broadcast a radio reading service for the blind, which reads articles in local newspapers and sometimes magazines. The vision-impaired can request a special radio, permanently tuned to receive audio on a particular subcarrier frequency (usually 67 kHz or 92 kHz), from a particular FM station.
Services like these and others on broadcast FM subcarriers are referred to as a Subsidiary Communications Authority (SCA) service by the FCC in the United States, and as Subsidiary Communications Multiplex Operations (SCMO) by the Canadian Radio-television and Telecommunications Commission (CRTC) in Canada.
Read more about this topic: Subcarrier
Famous quotes containing the word private:
“Public scandal is what makes the offense; sinning in private is not sinning at all.”
—Molière [Jean Baptiste Poquelin] (1622–1673)