The stereo-encoder is a fundamental device for
FM stereo broadcasting. The STC combines the signal of the left and right
channels to form the coded stereo (multiplex) signal using to the pilot-tone
method. The stereo broadcasting is made with the 19 KHz switching of two
channels (A and B). With this method (called time partitioning) the two channels
can be transmitted with a single transmitter. It contains a 50us Preemphasis
circuit (option 75us). The pilot frequency is obtained dividing by 2.432 kHz
crystal, thus ensuring a high frequency stability.
Stereo Coders 
