• Bad Autotune of 7010B - Due to electronical problems?

    Dear Community, the Autotune of my 7010B runs quite bad. The ramp plots (entrance lens, extractor, ion body, ion focus, post extractor) are scraggy. The mass peaks are fronting. In addition the GC-Runs are not repro...
    last modified by juliaalthammer
  • Problems tuning after installing new electron multiplier on Agilent 5975C

    My lab recently changed the filaments and installed a new electron multiplier on our Agilent 5975C. When I try to tune the peaks all seem like noise and then if gives me an error for the tune reading " Tune action Sto...
    last modified by aacos095
  • How do I change my autotune temperature settings?

    I'm using a 7890/5975 with an inert ion source - my methods and manual tune utilize a source temperature above 300 degrees and I want to match my autotune to that as well. Currently if I want to autotune, my MS d...
    created by srosoli
  •    the library search score for a compound is different with different instrument

      .the library search score for a compound is different with different instruments nowadays,in my work we have different types of gc-ms, we bought new gcms 7890B- 5977B HES , when comparing the result of the same...
    last modified by walleed
  • ?a new problem with front inlet shutdown in high efficient GCMS

     Dear colleagues      we encountered a new problem with front inlet shutdown in high efficient GCMS , the inlet itself appear OK before the beginning of run method and still OK during syringe ...
    created by walleed
  • Agilent 5975 MSD Autotune Report Readings

    I have couple of questions regarding Agilent 5975 MSD (run on MassHunter) Autotune Report. Please see the attached. It looks like for m/z 69, 219, and 502, there are two sets of data on the report. The Abund and Rel A...
    created by pcke2000
  • After cleaning, tune still not within limits for high mass

    We've had several issues with our 5977B MSD in the past few months. I recently spoke with the Agilent engineer that installed the instrument in January 2019 and he made the recommendation to replace the repeller and e...
    last modified by kbenzrihem
  • Molecule (melatonin) won't ionize with ESI, has anybody else run into this problem?

    I'm trying to identify melatonin and seratonin.  When I run the standards, each one has it's respective peak but it's the molecular parent ion, not a fragmentation that shows up.  I'm currently using ES...
    last modified by kebattaglia
  • How to shut down an Agilent GCMS for power fails up to long term storage 17Mar2020.pdf

    Here are directions on how to shut down an Agilent GCMS system for a short time up through longer term storage.
    last modified by m4esti
  • Agilent 7000A - MS Error 1.5

    Dear colleagues! Suddenly the new problem with our Agilent 7000A has appeared Instrument has worked quite intensively for a year in our laboratory (instrument has been bought refurbished 20 month ago). A month ago,...
    last modified by mag
  • Negative Mode - Peptides

    in LC-MS, i was wondering how does negative ionization  (Negative Mode) work with peptides? Same sample has shown differece in the intensity of the ionization, it is much lower in negative mode .. the negative is...
    created by weaam.dakda
  • Error running autotune on Agilent 5975C MS

    My filament burnt out during one of my runs so I went into tune parameters and switch to the second filament. The MS seems like it is working since I can see a light through the window when I turn it on. Unfortunately...
    last modified by aacos095
  • Optimizing Agilent Jet Stream source

    I'm looking for some reading material to help me how to understand the process of optimizing conditions for a AJS source.  I've inherited several methods in our teaching labs which seem to employ zero nozzle volt...
    last modified by javaslinger
  • System does not let me change values for small molecule tuning

    Hi I have tried to optimize our qtof (6550 iFunnel, AJS) for detection of small molecules. The Help Contents suggested some critical values for detection of low molecular weight molecules and I tried to change those v...
    created by joonseok
  • No change after cleaning MS

    Good afternoon everyone,   Over the last year, the EM volts of the MS have been slightly creeping up. Where it was still ~EMV 900 now we are roughly around 1800. Since we had a bit of downtime, there was a chan...
    last modified by koos
  •    dipping the quads

    how to dipping the quads i found the answer in   the 5975C troubleshooting and maintenance pg 159-160  . . 5975 Troubleshooting and Maintenance manual.pdf
    last modified by walleed
  • CO2 level is aroud 70% in the EI source

    Hello everyone! I am having a huge issue with CO2 level in the EI source of the MS. After the last time I had opened the source, when I tune the system tune evaluation report that N2 (7%), O2 (1%) and H2O levels are o...
    last modified by carolinejaegger
  • Has anyone had any experience optimizing the nebulizer needle distance from the nozzle for ESI applications, specifically peptides on the Agilent 6495B?

    We noticed that our nebulizer needle (G1946-67098) is flush with the end of the nozzle.  The Agilent "Nebulizer Adjustment Fixture" User Guide recommends a protruding distance of 0.003 inches (0.08 mm) for ESI.&#...
    created by padraigb
  • Collection of LC (HPLC)/MS Resources   

    Here is a "best of" collection of links to manuals and tools for LC/MS on Agilent.com, for other instruments refer to Collection of Support Documents on Agilent.com.   Collection of LC (HPLC)/MS Resources  ...
    last modified by rolanddiaz-bone
  • 5977A MSD Atune OK, Etune Falloff error 5977A MSD help?

    Good Day,   We have an issue with one of our instruments. it is a 5977A MSD and is fine on an Atune. All looks great.   However, during an etune (method specifically states this type of tune due to higher ...
    last modified by gchaplain