Chromatography Forum

MY 5972 recently took and electrical hit, and I had to replace the electronics board and the on/off switch breaker was blown. It is up and running now, and I just got finished fixing one calibration problem (I run 8270 semivolatiles). Now, what I am noticing is that the MS is not holding a tune (target). It will tune okay one day with a susequent DFTPP passing. The next day, the DFTPP will no longer pass. I also have last sensitivity at the low end for heavier phenols such as pentachlorophenol and App IX compounds such as Aramite. Any suggestions would be greatly appreciated.
Thanks,
Amy