PURPOSE: To detect the end of play securely by preventing malfunction in case that a record disk has eccentricity, by providing a Schmitt trigger circuit which operates only by a pulse within constant set-level range.

CONSTITUTION: In case that a record disk is eccentric, a pulse wave generated by photointerrupter 1 turns into a sine wave of large time width while slit 4a of shutter plate 4 cross a beam from light source 2. In this case, the falling voltage of Schmitt trigger circuit 5 is set to sufficiently low-level E5aL, and the rising voltage to sufficiently high level E5aH to make circuit 5 output a rectangular wave of time width t1, which is applied to monostable multivibrator 7 by way of differentiating circuit 6. Then, a rectangular wave of constant time width t2 is applied to terminal 8a of deciding circuit 8 and that of time width t1 is also applied to terminal 8b. As a result, circuit 8 generates no output and a tone arm never returns automatically in play due to malfuction.