System for transmission and reception of discrete four channel stereo
FM stereo demodulator
FM Stereo demodulating circuit Patent #: 4539697
AbstractA stereo signal separation system for separating the L+R and L-R components of a BTSC stereo signal mixes the BTSC signal with a multiple of the pilot frequency. To recover the L+R component the mixer output is combined with the input BTSC signal, and to recover to L-R component the mixer output is combined with a second mixer output shifted ninety degrees. The combined output is low pass filtered to recover the desired component.