Tuning

[Spectro]

Hi all,
I'm very frustrated on tuning my GC/MS. The target mass of 75 relative to mass 95 always failed off the range. I tried to do autotune and bfb tune but in vain. I really don'n know what to do next. Please advice.
Thanks all, Spectro.

[AICMM]

Spectro,

Post your tune, post your BFB maximum spectrum or your tune report. Without more data no one can really help you.

Best regards.

[Omaejel]

I have had problems with 75 creeping up near 95 and autotune and bfbtune not being able to bring the tune within limits. When this happens i generally clean the instrument and that solves the problem.

There was one instrument a few years ago that would not tune with the automated tune process regardless of which one you used. I wound up running a BFBtune and then adjusting it by hand to get it to tune. I just maximized everything using the ramp function and then went back and adjusted it to bring it back in line with what it should be. I fought it like this for a few months and then it just started working fine. I suspect it was either the repeller or a lens that was not sanded properly and eventually it got whatever was wrong worked out as it was cleaned, but who knows! These beasts are fickle sometimes.