在高中物理教材(必修加选修)第二册学生实验《练习使用示波器》一节中,有关“观察扫描情况”的叙述如下:“把 X 增益旋钮顺时针转到三分之一处,扫描微调旋钮反时针转到底,扫描范围旋钮置于最低挡。可以看到扫描的情形:亮斑从左向右移动,到右端后又很快回到左端。顺时针旋转扫描微调旋钮以增大扫描率,可以看到亮斑迅速移动成为一条亮线。调节 X 增益旋钮,可以看到 In the high school physics textbook (required for optional), the second volume of the student’s experiment “Practical use of an oscilloscope” is described in the section “Observing the Scanning Situation” as follows: “Turn the X gain knob clockwise one-third, scan fine-tuning Turn the knob anticlockwise to the bottom and the sweep range knob to the lowest level.You can see the scanning situation: the bright spot moves from left to right, and then quickly returns to the left at the right end. Turn the scanning fine adjustment knob clockwise to increase the scanning rate. , you can see the bright spot quickly move into a bright line. Adjust the X gain knob to see