I am working with a Varian Saturn 2000 which is out of cal. I have:

tried standard mass cal - doesn't work as the masses are too far upfield, i.e. 69 is at about 60, 131 is at about 120, etc.

I tried straight line cal followed by tuning with DailyCheck.mth using the RF full scale adjust. It won't adjust the 131 peak. I only reached about 125 m/z at the potentiometer upper limit.

Any suggestions?