问题 问答题 论述题

说明钢轨探伤仪无扫描线、无报警,荧光屏中心只有一个亮点应如何判定故障所在部位。

答案

参考答案:

此现象说明示波管各脚的电压和增辉电路正常,应用示波器重点检查各通道的工作信号和扫描电路是否正常。

探究题

       通过这学期的学习,我们了解了很多古代著名的历史人物,如治国名君、治世能臣、文学名家、能工巧匠等,相信你一定受益匪浅吧!他们中你最欣赏谁?说说你的理由。

                                                                                                                                                            

                                                                                                                                                            

                                                                                                                                                            

                                                                                                                                                            

                                                                                                                                                            

单项选择题