A contact pin comprises a plunger contacting an electric part, a bottom contact portion electrically connected to a printed circuit board, and a spring urging the plunger and the bottom contact portion so as to separate from each other, in which at least one of the plunger and the bottom contact portion is formed by press-working a plate member. 905 gcm3, a melt flow rate of 60 g10 min, a Rockwell hardness of 107, a Durometer hardness of 84, and a melting point of 330 F. A peak detection module identifies a plurality of peak samples from the plurality of interpolated read samples. Possible other inputs to the signal processing apparatus include the input optical power, test optical power, etc. A second implementation, error corrective training, can be used to estimate option weight when a sufficiently large number of utterances are available. In this way, when radio communication is performed by using beam forming, the time necessary for finding and setting a beam direction is reduced, thereby reducing the transmission-disconnected time.