Abstract: An optical disk player has a controller circuit board attached to a cartridge receiver. A universal head, actuator (head carriage) and spindle motor assembly (HASA) module is attached to the receiving mechanism. The actuator carries an optical head assembly along a predetermined path contiguous with a transducer access opening of a cartridge in the receiver and radially of an optical disk in the cartridge. A leaf spring is mounted in a bottom portion of the module and extends along the predetermined path toward a disk mounting spindle. The leaf spring has an upstanding end portion between the spindle and the predetermined path. While the head carriage is disposed closely to the spindle and the receiver is in a load-unload position, a detent on the head carriage is engaged in an aperture in the spring that is adjacent the upstanding end portion.