Abstract: A method and means for vertical interval encoding of a program signal having at least a video program portion with sequential fields separated by vertical intervals, the program signal having associated therewith sequential field related identification code signals, wherein a desired field related identification code at which encoding of the program signal is to commence is selected. Continuously recurring vertical interval code signals are generated at predetermined intervals corresponding to like intervals between groups of fields, for example two or three, of the program signal. The identification code associated with the program signal is then compared with the selected identification code, and upon the occurrence of a match of identification codes, the composite video program signal is signal-mixed with the vertical interval code signal in timed relationship so as to insert the vertical interval code signal in corresponding vertical intervals of the program signal.

Abstract: A signal conditioning method and apparatus for preconditioning an FM code signal prior to its processing by a limited bandwidth medium such as an audio magnetic recording track. The FM code signal is preconditioned to limit its bandwidth and alter its phase equalization prior to processing by the medium. The phase equalization is altered in a way opposite to the alteration performed subsequently by the limited bandwidth medium, such that the conditioned signal after recovery from the medium has substantially no phase distortion relative to the input signal and no high energy distortion. The invention is particularly useful when an FM code signal is to be mixed with an analog signal and the composite signal is first processed by a limited bandwidth medium and is then processed by a further analog medium, such as an FM modulator.