Stereophonic Separation in Transmission

This paper is primarily concerned with the stereophonic separation provided in a transmitted FM stereophonic signal. The equation derived, however, involves only parameters whose values are obtained from oscilloscopic displays of the composite stereophonic signal and is even more applicable to unmodulated composite stereophonic signals. There is a discussion of accuracy limitations imposed by methods and associated test equipment required for practical applications of the equation. It is pointed out that the so-called "pilot phase" [FCC Rules and Regulations 73.322(c)], should have a tolerance associated with it since it is one of the parameters involved in separation. A value of 500 nanoseconds is reasonable.