Hi Osborn

We meat the same situation before, as James said.

Beside that, there are two thing maybe you can check.

Is the version of Isodat service pack same as before?
Check the wires and pins of the ion source, do those loose or are too close to the magnet?

Good luck

Dr. Nai-Jung, Wan 萬乃容

H&N- Health & Nutrition健康暨營養事業群

3F,No. 125, Wu Kung Road, Wuku Industrial Zone, New Taipei City, Taiwan 24886

24886 新北市五股區(新北產業園區)五工路125號4樓

Phone: +886 2 2299 3279 Ext. 6703

From: Stable Isotope Geochemistry <[log in to unmask]> On Behalf Of Ball, James
Sent: Tuesday, March 9, 2021 12:44 AM
To: [log in to unmask]
Subject: [EXTERNAL] Re: [ISOGEOCHEM] IRMS Sensitivity

*** WARNING: this message is from an EXTERNAL SENDER. Please be cautious, particularly with links and attachments. ***

Box + Trap should = Emission.

If it does not it is a dodgy filament. Thermo sent out a batch of bad filaments several years ago.

Contact Giovanni at the Thermo help desk.

James Ball

School of Environmental Science

University of Liverpool

https://www.liverpool.ac.uk/earth-ocean-and-ecological-sciences/research/oceans-sciences/oceans-and-climate/facilities-and-services/lifer-lab/

From: Stable Isotope Geochemistry <[log in to unmask]> on behalf of Hill, Brett (AAFC/AAC) <[log in to unmask]>
Sent: Monday, March 8, 2021 4:01 PM
To: [log in to unmask]
Subject: Re: IRMS Sensitivity

Could it be that your focus settings have changed dramatically? What is the emission set at?

From: Stable Isotope Geochemistry <[log in to unmask]> On Behalf Of Osborne Malinga
Sent: Monday, March 8, 2021 8:16 AM
To: [log in to unmask]
Subject: [ISOGEOCHEM] IRMS Sensitivity

Dear list members

We had a software problem on our ThermoFisher Isotope Ratio Mass Spec DELTA V Advantage in January this year. We were forced to reinstall the software and all seem to be fine except the sensitivity of the MS. Before software problem the sensitivity was fine the Box current was reading 0.72mA and the Trap current was 0.76mA. After re-installing the software the Box current is 0.47mA and the Trap is 0.38mA. We tried to change filaments but that did not assist us. Is this problem has anything to do with MS configuration or the quality of the Filament? Please help us.

Regards

Osborn Malinga

Research Technician/Operator

Ithemaba LABS (Gauteng)

Email: [log in to unmask]

Tel : +2711 351 7000