According to the present invention, there is provided a low dielectric loss tangent resin composition containing a crosslinking component having a weight average molecular weight of not more than 1,000 and a plurality of styrene groups and represented by the formula 1, . The type of a recording disk is determined by a disk distinction unit of a microcomputer, and a reproduction processing is immediately started unless the recording disk is determined as a DVD. And also a frequency divider arranged to derive a second mixing signal from the first mixing signal.