Editing Multiplexing (section)

===Analog broadcasting===
In [[FM broadcasting]] and other [[analog signal|analog]] [[radio]] media, multiplexing is a term commonly given to the process of adding [[subcarrier]]s to the audio signal before it enters the [[transmitter]], where [[modulation]] occurs. (In fact, the stereo multiplex signal can be generated using time-division multiplexing, by switching between the two (left channel and right channel) input signals at an ultrasonic rate (the subcarrier), and then filtering out the higher harmonics.) Multiplexing in this sense is sometimes known as '''MPX''', which in turn is also an old term for [[stereophonic]] FM, seen on [[stereo system]]s since the 1960s.