HP 8753C A3 SOURCE问题

亲爱的同事们，您好！
我的HP 8753C网络分析仪出现问题。
F / W版本：04.13。
选项：NONE第一个问题是A3 Source。
我尝试检查服务手册中“源组故障排除”的“A3 SOURCE AND A11 PHASE LOCK CHECK”的输出。
我发现只有3.8 GHz -40 dBm的信号，略有几MHz的跳频。
该信号与VNA的预调频率无关。
除了3.8 GHz之外我没有看到任何其他谐波：在它之后我测量了腔体振荡器的信号并获得了具有更多功率的3.8 Ghz信号：大约+10 dBm。
因此腔体振荡器功能正常。
我还检查了YTO振荡器并没有看到任何信号。
我检查了所有电源轨，看起来很好。
所以我认为问题是有缺陷的YTO。
问题是如何在没有YTO的情况下测试A3 SOURCE模块的其他部分？
我尝试将0-3GHz 0dBm信号从发生器应用到A3 SOURCE而不是YTO，并在VNA的RF OUT端口用SA测量信号。
我可以看到来自发电机的信号，但也有很多谐波：100 MHz 0 dBm 500 MHz 0 dBm 1000 MHz 0 dBm 2000 MHz 0 dBm 3000 MHz 0 dBm是正常还是只能看到一个谐波来自发电机？
据我了解，我看到谐波混合组件。
它们应该在A3放大器中滤除吗？
谢谢所有回复的人！



     以下为原文

  Hello dear colleagues!
I have problems with my HP 8753C network analyzer. F/W version: 04.13. Options: NONE
The first problem is A3 Source. I tried to check the output regarding to "A3 SOURCE AND A11 PHASE LOCK CHECK" of Source Group Troubleshooting found in service manual.
And I found out only 3.8 GHz -40 dBm signal with slightly several MHz frequency hopping. This signal is independent of pretune frequency of VNA. I did not see any other hARMonics except 3.8 GHz:
  After it I measured the signal of Cavity oscillator and got  the 3.8 Ghz signal with much more power: about +10 dBm. So the Cavity oscillator is functional. Also I checked YTO oscillator and did not see any signal. I checked all power rails and they looks good. So I think the problem is defective YTO.
The question is how I can test other parts of A3 SOURCE module without YTO?
I tried to apply 0-3GHz 0dBm signal from generator to A3 SOURCE instead of YTO and measured signal with SA at RF OUT port of VNA. I can see the signal from generator, but there are many harmonics as well:
      100 MHz 0 dBm             500 MHz 0 dBm            1000 MHz 0 dBm           2000 MHz 0 dBm           3000 MHz 0 dBm

Is it normal or should I see only one harmonic going from generator? As I understand it I see harmonic mixing components. Should they be filtered in the amplifier of A3?

Thank you to everyone who will respond!