JPS5476105A - Information reproduction system - Google Patents

Abstract

PURPOSE:To perform reading at a high speed by the use of a light source of a small capacity by detecting that the vibrations of a motor have become less than a specified magnitude thereby starting reading-out. CONSTITUTION:A motor driving circuit 5 consists of a DC amplifier 5 and parallel- connected feedback resistances 52, 53 and a transistor Tr 11 is series-inserted into the resistance 53. The base voltage (g) of the Tr 11 gradually increases as the vibrations of the motor decrease, and at the time (t), the Tr 11 goes ON. As a result, the circuit 5 is changed over from one resistance 52 to the two parallel resistances 52, 53 to be lowered of its resistance, due to which the gain attenuates and the vibrations of the motor 1 stop. When the vibration amplitude of the motor 1 becomes within a permissible value, a Schmitt circuit 12 generates a read-out timing pulse. This timing pulse causes the read-out means to start actuating, thence the information is read out from the assigned address of a recording medium 2. Thereby, the reading-out may be performed at a high speed by the use of a light source of a small capacity.