Question

为了让电磁波传递信号,可以：

(1)使高频电磁振荡的振幅随信号而改变,此过程叫__________.

(2)使高频电磁振荡的频率随信号而改变,此过程叫__________

A.检波                 B.调幅             C.调谐              D.调频

Answer 1

(1)B  (2)D