219 Low Abundance

[gpronger]

Why don't you print and post the profiles of the lens, particularly the repeller, ion focus, entrance lens, and entrance lens offset.

My guess is that there is something amiss with one of the lens.

[gpronger]

Why don't you print and post the profiles of the lens, particularly the repeller, ion focus, entrance lens, and entrance lens offset.

My guess is that there is something amiss with one of the lens.

[BCBC]

I see no notes but I believe the low 219 was a result of the abundance of water. Once that pumped out things were better.
219 abundance is somewhere around 55 %. It never has been exceptional even with multiplier or source change.

[aldehyde]

If you lift up near the back of the analyzer door, at the hinge, it will lift out of position and allow you to remove the analyzer. If it needs to sit out for a bit cover it with a lint free cloth or two. Keep in mind the coating on the quads is hygroscopic, you won't kill it by letting it sit out for awhile but dont leave it in a room with high humidity .

[aldehyde]

yeah water will kill your abundances.

[JI2002]

The issue here is low ratio of m/z 219 to m/z 69, not the absolute abundance. Water doesn't just affect m/z 219. You need to follow gpronger's advice and do manual tune.