Track control circuit for optical card recording/reproducing apparatus

A track control circuit for an optical card recording/reproducing apparatus, comprising:

• light beam means for emitting a light beam for optically recording/reproducing information onto a card-like optical recording medium having a plurality of tracks;
• focusing means for focusing the light beam emitted from said light beam means onto said card-like optical recording medium;
• photosensing means for detecting a beam reflected by a desired track of said card-like optical recording medium;
• error signal generating means for generating a track error signal output in accordance with a deviation of the reflected beam detected by said photosensing means;
• actuator means having a moving member which is movable across said tracks;
• track scanning means for driving said actuator means by transmitting a track scanning signal to said actuator means, in a state wherein said actuator means is stopped relative to said card-like optical recording medium, thereby to perform a track scanning operation wherein the light beam moves across said tracks;
• track servo means for holding the light beam on said desired track, by transmitting the track error signal to said actuator means so that said actuator means uses the track error signal in replacement of the track scanning signal;
• gain setting means for setting a gain of the track error signal;
• determining means for determining that the track error signal is abnormal when an amplitude level of the track error signal differs from a predetermined amplitude level during the track scanning operation, and for determining that the track error signal is normal when the amplitude level of the track error signal is equal to the predetermined amplitude level during the track scanning operation;
• and
• control means for outputting to said gain setting means a control signal for controlling the gain set by said gain setting means, only when said light beam means is stopped relative to said card-like optical recording medium and when said determining means determines that the track error signal is normal, and, when said determining means determines that the track error signal is abnormal, moving the light beam across said tracks again after moving said actuator means relative to said card-like optical recording medium.