AM stereo is the name of a method for transmitting stereophonic signals over radio stations in the long, medium or short wave range. Because of the low available bandwidth and the compatibility requirement, the FM stereo method used in the VHF range for stereo transmission in this frequency band is not applicable.

The encountered in North America usual method of AM stereo Motorola C- QUAM.


The amplitude-modulated signal includes the sum of information of both channels. It can be received by any conventional radio for long, medium and short wave. To get to the stereo information, one has to demodulate the transmitted according to the method of quadrature modulation difference signal of the two channels, and to assemble the information thus obtained with a suitable decoding circuit, and with the sum signal of the signals for both channels.


AM stereo is not applied in Germany. In the United States, South Africa and Australia it is widespread. In Europe, the process is used by the night -to-air broadcasters in Germany by France Bleu on 864 kHz in Villebon -sur -Yvette and the Italian Radio Studio X on 1584 kHz.