| 摘要 |
A system for recording audio and video signals on magnetic and other media including a generator of a time-reference square-wave signal, a circuit for combining the dc level with an input audio or video signal, and a sampling circuit wherein the sum of the input signal and the dc level are sampled in synchronism with the square-wave signal. The time-reference signal and a second signal, delayed therefrom, are then recorded by saturation of the magnetic medium in both positive and negative directions. The amount of delay between the two recorded signals is proportional to the amplitudes of the successive samples of the sampling circuit. After playback, the original input signal is retrieved from the recorded signals by comparing successive samples with a succession of ramp waveforms and filtering out the sampling spectrum and the dc level.
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