| 摘要 |
<p>PURPOSE:To eliminate the unpleasant feeling such as sound in operation of tone arm control of a record player, by combining and applying a suitable number of step signals obtained via a time integration circuit so as to turn a stepping motor SM. CONSTITUTION:Four sets of pulse train step signals are provided and applied to phases A, B anc the like of the stepping motor SM after amplification as required. In this case, the four pulse train step signals are timewise integrated with the inductance of the exciting coil of each phase. When the tone arm TA is driven with the SM, in the mechanical oscillation of a stand B mounting a pickup cartridge, a rotary angle at each step or a moving distance is only delivered and the transient waveform disappears.</p> |
