A.功率 B.電流 C.電壓 D.直流
A.微分電路后產(chǎn)生尖脈沖 B.積分電路后產(chǎn)生尖脈沖 C.微分電路后產(chǎn)生鋸齒波 D.積分電路后產(chǎn)生鋸齒波
A.60° B.90° C.120° D.180°