PURPOSE:To positively control the locations of a tone-arm by a simple structure, by applying motional feedback operation as well as positional servo-operation in relation to a tone-arm device used for an automatic record player. CONSTITUTION:When a tone-arm 1 moves along a sound groove and reaches a fixed location, the location is optically detected by means of a positional detector 38. If the reference value of a positional servo-output circuit 39 is beforehand let correspond to the target location because the output of the detector 38 rectilinearly increases with the access of a window 35 of a shutter 34 to a light source, the circuit 39 supplies positional servo-signals to an amplifying and servo-circuit 33 forming a motional feedback MFB circuit with each coil 22, 23 for horizontal detection and horizontal drive when detecting signals from the detector 38 reach the reference value. The output is fed to the coil 23 for horizontal drive of the arm 1 and applies positional servo-operation, but the locations of the arm 1 can positively be controlled because the positional servo-operation can be executed while MFB remains as it is applied.
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