HP 8753A称“仪器状态记忆已清除”

我的回忆有点昏暗，但我相信这是指仪器状态记忆。
我记得，我们有EPROM，EEPROM和一些CMOS静态RAM以及动态RAM。
固件在EPROM中，硬件服务测试结果在EEPROM中，用户状态和校正在CMOS静态RAM中。
静态RAM通过“超级上限”保持活动状态，可以使其保持活动状态至少3天。
因此，如果8753A打开并且没有错误地扫描（记得将源连接到R通道）那么它很好。
但是，它已经快26年了，所以有些硬件可能已经漂移了，并且必须重新运行一些服务测试，特别是phas-lock cal和source cal，这并不罕见。



     以下为原文

  My recollection is a little dim, but I believe that refers to the instrument state memory.  As I recall, we have EPROM, EEPROM and some CMOS static RAM as well as dynamic RAM.  The firmware is in EPROM, the hardware service test results are in EEPROM, and the user states and corrections are in CMOS static RAM.  The static RAM is kept alive with a "super-cap" that can keep it alive for a minimum of 3 days.  

So, if the 8753A turns on and sweeps without error (remember to connect source to R channel) then it is fine. BUT, it is almost 26 years old, so it is likely that the some of the hardware has drifted and it is not unusual to have to re-run some service tests, particularly phas-lock cal and source cal.

谢谢Dr_joel，我和我的朋友说过，他说它确实在扫描，但他对校准不满意。
如果他进行校准，并查看直通连接，则频率响应会出现峰值。
我不认为他已经使用了一段时间，所以他对确切问题的记忆并不是很好。
他也有S参数测试集。
我们打算做什么，是他带着他的VNA给我，我们交换VNA，电缆和S参数测试装置，试图确定至少可能有什么位错。
他想知道它的S参数测试装置是否没有正确切换。
无论如何，希望我们可以尝试解决这个问题。



     以下为原文

  Thank you Dr_joel, 

I spoke to my friend and he said it does scan, but he is not happy with the calibration. If he calibrates, and looks at a thru connection, there are spikes in the frequency reponse. I don't think he has used it for some time, so his memory of the exact issue is not great. 

He has the S-parameter test set too. What we intend doing, is him bringing his VNA over to me, and we swap the VNA, cables and S-parameter test set to try to ascertain at least what bit may be at fault. He is wondering if its the S-parameter test set not switching properly.  

Anyway, hopefully we can try to sort this out.

PS，我应该补充一下，他说当打开设备时会出现错误信息，但如果触摸了按钮则会消失。
戴夫



     以下为原文

  PS, I should have added, he says the error message comes on when the unit is switched on, but dissapears if a button is touched. 

Dave

戴夫，失败就像乔尔博士所说的那样。
由于信号在加电时丢失，因此动态Ram被清除。
这是SuperCap故障或该板上RAM负载泄漏电路的结果。
只要EEPROM处于保护模式，设备上的所有重要对齐信息都是完整的。
您只需松开存储的配置设置，以及存储在RAM中的任何其他信息与工厂标准配置不同。
如果您运行自检0，则可能会显示失败。
在尖峰上，这可能与痕量噪声有关。
运行自检17,18和19.这将测试A10组件上的ADC电路。
如果该板出现故障，则会导致峰值。
此外，一些尖峰是频率相关的和信道相关的。
如果你可以说明噪声的频率和频率，这将隔离失败的可能性。
该单元也可能需要对齐以纠正这些故障。
服务指南会列出调整和相关性能测试，以查看设备是否正常工作。



     以下为原文

  Dave,

That failure is as Dr. Joel stated.  The Dynamic Ram is cleared as the information is lost on power up.   This is a result of the SuperCap failure or leaking circuitry on the RAM load on that board.   As long as the EEPROM is in the protected mode all of the important alignment information on the unit is intact.  You just loose the stored configuration set ups, and any other information stored in RAM different from factory standard configuration.   If you run self test 0 this may show you the failure.  On the spikes, this could be related to trace noise.  Run Self Test 17, 18 and 19.  This tests the ADC circuitry on the A10 assembly.  If this board fails, this will result in spikes.  Also, some spikes are frequency dependent and channel dependent.  If you could state channels and frequency on noise this would isolate failure possibility.  The unit also may need alignment to correct those failures also.  The service guide does list the adjustments and related performance tests to see if the unit is working correctly.

谢谢。
我把它转发给了我的朋友。
我希望他可以运行自我测试来试图找出问题所在。
我今天收到了服务手册的副本（我更喜欢纸张到PDF）。
所以希望这会有所帮助。
幸运的是，他有一个相当广泛的测试实验室，所以希望能够解决它。
我会保留我的HP 8753A，直到我的朋友将他排除在外。
然后，如有必要，我们可以比较测量结果。
戴夫



     以下为原文

  Thank you. I've forwarded this to my friend. I expect he can run the self-tests to try to isolate the problem. 

I got a copy of the service manual today (I prefer paper to PDF). So hopefully that will help.  Luckily he has quite an extensive test lab, so will hopefully be able to sort it out. 

I'll keep my HP 8753A until such time as my friend sorts his out. Then if necessary we can compare measurements and results. 

Dave