| 摘要 |
<p>PURPOSE:To obtain highly accurate revolution stability by flashing a display element by means of the output which comprises dividing the crystal oscillation frequency used for the control reference of a quartz lock direct drive motor down to low frequencies. CONSTITUTION:The output which comprises reducing the oscillation frequency of a crystal oscillator 5 used for the control reference of the motor with a frequency divider 6 is further reduced to several Hz to 1 Hz with a frequency diveder 14. The AND of the output of said frequency divider 14 and the output of a window comparator 17 is obtained in a circuit 15 and the output of the frequency divider 14 only within the phase control region is directly outputted to the next stage. On the other hand, when it is out of the region, the output is reset. The output of this circuit 15 drives a driving circuit 16 which in turn flashes the dispaly element provided on a housing. Flashing of the display element stops when the phase control is released. In this way, the dispaly element may be flashed by directly dividing down the crystal oscillation output used for controlling of the motor and at the same time highly accurate revolution stability and superior wow and flutter characteristics may be obtained.</p> |
