| 摘要 |
<p>PROBLEM TO BE SOLVED: To form a magnetic recording and reproducing device capable of obtaining a satisfactory reproduced output by constituting a gap smaller than a specificμm between the lower edge of the slidable contact surface of a lower drum and a lead ring. SOLUTION: The deterioration of reproduced outputs from rotary magnetic heads when the gap Ga between the lower edge of the slidable surface of a lower drum Dd and a read ring Lr changed is shown from experimental results. Black round marks show measured values obtained at the fast-rewinding reproducing operation of a seven-fold speed using a rotary magnetic head whose head track width is 58μm and black square marks show measured values obtained at the fast-forwarding reproducing operation of a seven-fold speed using a rotary magnetic head whose track width is 58μm. In both cases, when gaps between the lower edge of the slidable contact surface of the lower drum Dd and the lead ring Lr are <=150μm, deterioration of reproduced outputs is <=-2db and when the gaps are >=150μm, the deterioration of the reproduced outputs is made to be larger. Thus, the satisfactory reproduced output is obtained by constituting the gap Ga smaller than 150μm.</p> |
