Chromatography Forum

Hi to everyone,

i'm having some trouble when running the autotune of my DSQ II GC/MS. When I run the default autotune (RF frequency calibration, detector gain calibration, resolution calibration (positive ions), full automatic tune and leack check), the system fails to pass the detector gain calibration (error: cannot perform gain calibration). I tried to unflag the gain calibration, but it still fails to pass the autotune (the message says "creating tune report for positive ions" and "error: cannot calibrate resolution). I tried to find some answer on the Thermo Fisher manuals, but they don't say much about autotune failures. I read a previous discussion here that said the problem could be in the lens voltage in the MS, but the readings from the instruments barely differs from the set values. Can some explain me what is wrong with my GC/MS?? Thanks a lot!!

have you tried cleening the system?
Problem might be caused by heater PCB and/or lenses that are dirty

Did you run the multiplier test in Diagnostics?

I had this issue for months! Run diagnostics in your tune software. If they pass, try the following:

Run air/water, background and FC43. If you don't see anything check (top up?) your cal gas, rinse and repeat
Clean your dirty ion source
Up your detector gain (but not too much, I think it shouldn't ever go above 2000??)
Still nothing? Check your filament's glowing (just take the top off)
Still bad? Maybe it's your S/N ratio? Replace / cut your column

Oh and call thermo, they can help you with diagnostics over the phone. I kept sending them screen caps of my complete lack of signals.

Hi,

for me it failed in this phase because I had a bad contact with Lens 1. After correcting that i still got calibration failed because i tried to do it too early. Even if it shows 50mTorr, you should let it rest for a couple of hours after a cleanup.

Regards