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@ -14,7 +14,9 @@ It seems that U008 was the culprit. I have a feeling that the failure mode had s
![ac fix](3458-WorkLog/imgE.png) ![ac fix](3458-WorkLog/imgE.png)
## Replacing the capacitors ## Replacing the capacitors
To save the meter from an early demise, I replaced all the capacitors, and indeed some seemed to be leaking already, I was lucky to replace them before the corrosion got worse. Another healthy upgrade I did was to update the firmware to the latest version, which improved the accuracy of the meter to some extent due to the various mathematical updates to said firmware. To save the meter from an early demise, I replaced all the capacitors, and indeed some seemed to be leaking already, I was lucky to replace them before the corrosion got worse.
![LeakyCap](3458-WorkLog/imgF.png)
Another healthy upgrade I did was to update the firmware to the latest version, which improved the accuracy of the meter to some extent due to the various mathematical updates to said firmware.
## Final bugs ## Final bugs
Now that the meter seems to be working, I tried ACAL with the meter after letting it run, and now it shows me an error I have never seen before. error 204 flatness dac convergence 199. The error occurs while the meter is warming up and the ACAL step is always 100V. This immediately made me suspect the HV attenuation part, mainly the DAC. Cooling the board slightly, and seeing which component cooling makes it work, made me suspect U302, the LT318 op-amp behind the DAC. However, after replacing it with a different one, the problem still seemed to persist deterring me from assuming the fault is U302. Now that the meter seems to be working, I tried ACAL with the meter after letting it run, and now it shows me an error I have never seen before. error 204 flatness dac convergence 199. The error occurs while the meter is warming up and the ACAL step is always 100V. This immediately made me suspect the HV attenuation part, mainly the DAC. Cooling the board slightly, and seeing which component cooling makes it work, made me suspect U302, the LT318 op-amp behind the DAC. However, after replacing it with a different one, the problem still seemed to persist deterring me from assuming the fault is U302.
![amprep](3458-WorkLog/imgC.png) ![amprep](3458-WorkLog/imgC.png)