The delta sound system for television receivers

The delta sound system for television receivers incorporates the three features of AM compression, high-level audio output FM detection, and fundamental AM cancellation in a circuit having cost advantages. Design information is presented for the system to enable the circuit designer to specify component parts and to predict the performance. AM compression in the range of 12 to 24 db and a peak-to-peak audio output voltage of about 60 volts with cancellation of the fundamental component of the undesired AM are obtainable with readily available low-cost tubes and circuit components.