| 摘要 |
PURPOSE:To prevent a record and a record stylus from being damaged even in case of unexpected power failure by providing an arm drop control circuit in an arm driving system of a record player. CONSTITUTION:An arm driving current is flowed in the arm drop control circuit in directions of dotted arrows in the normal case and is flowed there in directions of solid arrows at the stop time. That is, in the normal case, a power source is turned on to turn on a transistor (TR) Tr1 with a voltage obtained by dividing a voltage Vcc by resistances R1 and R2, and a Tr2 is turned off, and therefore, a capacitor C1 is charged by resistances R3 and R4. The resistance R4 has a sufficiently large resistance value and has no influences upon the normal operation. When power failure occurs, the Tr1 is turned off by the break of the voltage Vcc, and the Tr2 is turned on, and therefore, the electric charge charged in the capacitor C1 is discharged to an arm driving coil as the driving current to prevent quick drop of the arm.
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