82 5975 Series MSD Operation Manual for MassHunter
3 Operating in Electron Impact (EI) Mode
Results will indicate the recommended amount to adjust AMU offset for
high-mass. If your results are within 5 units of the targeted amount, there is no
need to make adjustments.
Adjustments
1 Verify ATUNE.U has been loaded.
2 In Instrument Control view select Edit Tune Parameters from the Instrument
menu to display the Manual Tune dialog.
3 Click the Dynamic tab and then click the Amu Offset sub-tab.
4 Select the Enable This Lens checkbox.
5 Enter the recommend dynamic offset Voltage (V) and click OK.
6 Click Save to save this dynamic Amu Offset for the high-mass.
You can overwrite the existing ATUNE.U to include high-mass adjustment
or save this file to a new name, for example, ATUNEHIGH.U.
Anytime an ATUNE.U is performed, it will overwrite this dynamic Amu
Offset that was entered. This is why you might want to rename the tune.
7 Click Done to close the Manual Tune dialog.
8 Load the PFHT.M, then load the saved tune file, and then save the method.
9 Rerun test mixture (repeat high-mass checkout). If the correction is within
5 units, no further adjustments are required.