SCHALTUNG FUER PLATTENSPIELER ZUM DREHEN DES PLATTENTELLERS IN EINE BESTIMMTE AUSGANGSPOSITION

摘要

In order to start a disk exactly at a syllable, the turntable (2) must be turned back by a certain angle. For this purpose, use is made of a reversible motor (1), which is coupled to a tacho-generator (3). A central speed control unit (4) controls the motor (1). By activating the actuating member (10), the turning back of the turntable (2) commences at 0.707 of the nominal speed under the effect of a memory (11), an adjusting member (9) and the control unit (4). At the same time, a memory capacitor (13), which is connected to a threshold discriminator (14), is charged. At the end of the acceleration phase, a signal is generated by the discriminator (14), with the result that the motor (1) is driven in the opposite direction, that is to say it is retarded. Then, a braking magnet (20) is actuated, which magnet holds the turntable (2) securely in the desired position. <IMAGE>