METHOD AND MEANS FOR DIRECT-CURRENT POLARITY RESTORATION IN MAGNETIC RECORDING

A method and means is disclosed for restoring the direct-current component of a signal read from a storage medium in the form of isolated analog signals which are simultaneously applied to a differentiator and a binary signal generator. The positive pulses of the analog signals trigger the binary signal generator that produces binary signals which initiate and terminate offset signals provided by an offset signal generator. An offset signal is summed differentially with the differentiated analog signal, providing a reconstructed signal which is applied to a zero-crossing detector which produces an output that is either a logical high or low, and that is capable of being processed by digital techniques. The positive-going transitions in the binary signal are equivalent to level transitions of an originally recorded signal.