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5977 tune problem

Posted: Sat Feb 15, 2014 10:05 pm
by thohry
Hi all, our new instrument 5977 cannot pass autotune and the scan seem strange as follow:

Image

The vacuum is OK.

Could anyone help me on this

Thank you

Re: 5977 tune problem

Posted: Tue Feb 18, 2014 3:55 am
by bisnettrj2
Reposting the picture, it didn't display for me in the Forum.

Image

Re: 5977 tune problem

Posted: Tue Feb 18, 2014 3:38 pm
by Steve Reimer
What is your peak width? Does the ion focus maximize at something other than the upper limit? Is the repeller voltage something reasonable (<35V)?
Your 502 and 503 look like the same peak same you are not resolving your masses.

Re: 5977 tune problem

Posted: Wed Feb 19, 2014 7:29 pm
by James_Ball
What is your peak width? Does the ion focus maximize at something other than the upper limit? Is the repeller voltage something reasonable (<35V)?
Your 502 and 503 look like the same peak same you are not resolving your masses.
Not seeing much 131 at all either, there should be as much of that as there is 69.

The peak widths look quite wide except for 69, or it is just a lot of noise.

I have never looked at a tune from Mass Hunter, which I am guessing this is, but is doesn't look that good either way.

Looks as if the peaks are fronting, which usually means a problem such as dirty quads or a lot of moisture.

Can you do a profile scan of 69, 219 and 502 and post the peak shapes for those masses?

Re: 5977 tune problem

Posted: Thu Feb 20, 2014 4:06 pm
by thohry
Thanks all for inputs.
I have tried all possible. It seem the peaks are not stable, it cannot focus at the exact place.
The CE said, it's due to faulty side board.
We'll wait and see.

Re: 5977 tune problem

Posted: Fri Feb 28, 2014 1:43 am
by thohry
Finally, the MSD is OK and it's due to the quadrupole itself, a miss-alignment.

Re: 5977 tune problem

Posted: Fri Feb 28, 2014 2:55 pm
by James_Ball
Finally, the MSD is OK and it's due to the quadrupole itself, a miss-alignment.
Wide peaks are normally a sign of problems in the mass filter, glad it was just a misaligned quad and not the side board. :)