One of our customer GC MS/7890B 7000C with extractor source was working well.
But after stopping for a certain period & trying again now the sensitivity was decreased & not comes to the previous one.
we made cleaning of ion source 3 times while changing the extractor with new one & change the detector.But there is no sensitivity improvement as previous one.
Even the sensitivity of tune with inert source mode was better than with extractor mode one.
what will be the probable cause of decreasing in sensitivity like this?
For more information please look on attached tune file of the previous one & present one.