从下往上 一行 代表什么意思？从左到右呢？
Using the test port extension cable and 30 dB attenuator, connect the signal
source to the input of the attenuator, and connect the output of the attenuator to
the RF In test port of the MS2711D.
Step 3. Press the AMPLITUDE key and select the Ref Level soft key to set the reference
level to –50 dBm.
Step 4. Select the Ref Level Offset soft key to set the reference level offset to –30 dB.
Step 5. Press the Scale soft key and set the scale to 10 dB/division.
Step 6. Press the Atten/Preamp soft key followed by the Dynamic soft key to use dynamic
attenuation.
5

楼主这是直接接什么信源，功率这么大！
使用测试端口延长电缆和30 dB衰减器，连接信号源的衰减器的输入端，和衰减器的输出端连接到射频在MS2711D的测试端口。
步骤3.按AMPLITUDE键并选择参考电平软键设置参考一级至-50 dBm的。
步骤4.选择的参考电平偏移软键设置参考电平偏移到-30 dB。
第5步.按Scale软键，并设定比例至10 dB /格。
步骤6.按安泰信/前置放大器软键，然后按动态软键，使用动态衰减。

谢谢你的回复，这个是安立扫频仪 操作手册上的一张图，他是安装步骤进行设置，然后生成了这张图。但是我一直看不懂。看了好几天了.

谢谢你的回复，这个是安立扫频仪 操作手册上的一张图，他是按照步骤进行设置，然后生成了这张图。但是我一直看不懂。看了好几天了.说明书上写的是 输入为-85dbm的信号，非常的微弱啊

Step 1. Reset the MS2711D to the factory default settings for the current mode by pressing
the RECALL SETUP key on the data keypad. When the key is pressed, a
Recall Setup selection box appears on the display. Select setup location 0 <Default>
to recall the factory preset state for the currently selected mode.
Step 2. Using the test port extension cable and 30 dB attenuator, connect the signal
source to the input of the attenuator, and connect the output of the attenuator to
the RF In test port of the MS2711D.
Step 3. Press the AMPLITUDE key and select the Ref Level soft key to set the reference
level to –50 dBm.
Step 4. Select the Ref Level Offset soft key to set the reference level offset to –30 dB.
Step 5. Press the Scale soft key and set the scale to 10 dB/division.
Step 6. Press the Atten/Preamp soft key followed by the Dynamic soft key to use dynamic
attenuation.
Step 7. Press the BW/SWEEP key, press the Bandwidth soft key, and press the RBW
Auto and the VBW Auto soft keys.
Step 8. Press the MEAS key and press the Channel Power soft key.
Step 9. Select the Center Freq soft key and set the center frequency of the Spectrum
Master to that of the GSM signal, in this case 947.4 MHz.
Step 10. Select the Int BW soft key and enter 200 kHz for the integration bandwidth, or
set the integration bandwidth appropriate for the particular application.
Step 11. Select the Channel Span soft key and enter 800 kHz as the channel span, or set
the channel span to a value appropriate for the particular application.
Step 12. Make the measurement by pressing the Measure soft key. The detection
method is automatically changed to RMS Average. Solid vertical lines are
drawn on the display to indicate the integration bandwidth. The MS2711D will
display the measurement results in the message area.
Figure 5-3 shows the results of the measurement using a GSM signal source with an output
power level of –85 dBm.

看信号源的输入大小，另外，你这个不是扫频仪，安立的扫频仪ML8740，ML8780在国内基本没有，因为太落后了