Digital magnetic recording and reproducing circuit for suppressing generation of asymmetry

A magnetic recording and reproducing circuit comprising,

• a recording and reproducing head means for record and reproduction on a recording medium;
• an erasing head means for DC erasing a track of said recording medium in a predetermined direction prior to recording;
• a record driver means for causing a recording current to flow through said recording and reproducing head in response to pulse-shaped record data;
• an erasing means for causing a DC current to flow through said erasing head;
• a flip-flop means which sequentially reverses the state in accordance with pulses of said record data;
• a delay means for delaying the rise of one of the outputs of said flip-flop means by a first time and the fall of the one of the outputs of said flip-flop means by a second time;
• and
• an exclusive OR means for providing an exclusive OR output of the output of said delay means and the other of the outputs of said flip-flop means, said exclusive OR output being input to said record driver means as compensated record data.

A magnetic recording and reproducing circuit comprising,

• a recording and reproducing head for effecting record and reproduction on a recording medium;
• an erasing head means for DC erasing a track of the recording medium in a predetermined direction prior to recording;
• a record driver means for causing a recording current to flow through said recording and reproducing head in accordance with record data pulses;
• an erasing means for causing a DC current to flow through said erasing head;
• a flip-flop means which reverses the state in accordance with the record data pulses;
• a first delay means for delaying the rise of the outputs of said flip-flop means by a first time;
• a second delay means for delaying the fall of one of the outputs of said flip-flop means by a second time which is different from the first time;
• and
• an exclusive OR means for providing an exclusive OR output of the output of said first and second delay means, said exclusive OR output being input to said record driver means as corrected record data pulses.