电视机中信号通道中的AGC控制方式是()。
A、控制高频通道增益
B、控制中频通道增益
C、先控制中频增益,然后再控制高频通道增益
D、高频通道增益和中频通增益同时控制
参考答案:C
选择括号内恰当的单词或词组填入空白处,使句意完整、正确。
— What’s your ___小题1:____ (favorite / like) sport?
— Basketball.
— How tall is Yao Ming?
— He is 2.26 meters __小题2:____ (high / tall).
—___小题3:___ (Hurry / Stand) up, or we'll be late for the meeting.
—OK. Let's go.
— Would you mind ____小题4:____ (to teach / teaching) me?
— Not at all.
— I’m sorry ____小题5:___ (for / at) what I said?
— It’s nothing.
在再热器水压试验完毕后,开启疏水门,缓慢降压。压力降至()MPa时,开启各空气门和疏水门。