E4448A频谱分析仪校准失败

嗨 - 显示的错误表明仪器的低频段路径有问题。
具有这些症状的最可能的失败是机械衰减器故障。
当仪器运行其内部校准时，它会打开50 MHz校准器并切换输入路径，以便此信号一直通过RF到达数字IF组件。
如果信号未通过整个路径，则仪器将无法进行多次内部校准。
建议将此仪器送至安捷伦服务中心进行维修。
问候 -



     以下为原文

  Hi -

The errors shown indicate that there is something broken in the low band path of the instrument.  The most likely failure with these symptoms would be a mechanical attenuator failure.  When the instrument runs its internal alignments, it turns on the 50 MHz calibrator and switches the input path so that this signal passes through the RF all of the way to the digital IF assembly.  If the signal doesn’t make it through the entire path, then the instrument will fail several internal alignments.  

It is recommended that this instrument be sent in for repair at an Agilent service center.

Regards -

我还读了一篇关于DRO需要更换的文章，可能是原因。
你对此有所了解吗？



     以下为原文

  I also read an article about the DRO needing to replaced and could be the cause.
Do you know anything about that?

以下是有关上一个回复的链接。
http://cp.literature.agilent.com/litweb/pdf/E4448A-15.pdf



     以下为原文

  Here is the link in regards to the previous reply.

http://cp.literature.agilent.com/litweb/pdf/E4448A-15.pdf

嗨 - 如果DRO /第二个LO失败，那么第一个对齐失败将是第二个LO功率电平。
错误队列显示顶部的最后一个错误，因此您必须单击“下一页”并向下看底部。
从发送的屏幕截图中，我没有看到错误，“-340，校准失败，ALIGN_2ND_LO_PWR”。
所以，我认为DRO / 2nd LO不是问题所在。
第二LO功率对准不使用主RF路径。
相反，它由低频带组件感测，并由低频带组件上的可变增益放大器补偿。
希望这可以帮助 -



     以下为原文

  Hi -

If the DRO / 2nd LO failed, then the very first alignment failure will be for the 2nd LO power level.  The error queue shows the last error at the top, so you have to click on the Next page and look down at the bottom.  From the screen shots sent, I didn’t see the error, “-340, Calibration Failed, ALIGN_2ND_LO_PWR”.  So, I don’t think that the DRO / 2nd LO is the problem.  The 2nd LO power alignment doesn’t use the main RF path.  Instead it is sensed by the low band assembly and is compensated for by the variable gain amplifier on the low band assembly.

Hope this helps -