DETECTION CIRCUIT FOR STEREO IDENTIFYING SIGNAL

摘要

PURPOSE:To speed up the detection speed, by integration after shaping of an identification signal. CONSTITUTION:An identification signal, in about 5Hz of an AM stereo broadcast is picked up from a low-pass filter 31 and applied to a limiter circuit 32. The output of the limiter circuit 32 is given to one input of an exclusive logical sum 33 directly and to other input via a delay circuit. The exclusive logical sum circuit 33 makes differentiation and wave shape substantially. As a result, the detection of identification signal for a stereo broadcast can be made, by integrating obtained pulses and giving it to the input of a Schmitt trigger.