If the mass scan shows peaks and they appear to be of reasonable 
magnitude, save your old focus, put all focus settings at default for 
linearity (something like 75% emission, max extraction, and 50% for all 
optics), then peak center, then autofocus...that is, it could just be 


Andrew Schauer
Earth and Space Sciences
University of Washington
Seattle, WA 98195

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On Sun, 11 Jul 2010, Thomas Millican wrote:

> Before checking for magnet orientation or loose or touching wires (and
> they will move a tiny bit onto the springs when the source assembly is
> inserted into the mass spec), a quick check is to just run a magnetic scan
> across the range of masses the machine is designed for and see if you get
> anything.
>> I removed and cleaned the ion source for our delta V advantage. I changed
>> a
>> new filament and I put back the source and everything looks fine on isodat
>> screen. Values are???
>> HV= 3.01KV
>> Box= 0.72 mA
>> Trap= 0.77 mA
>> vacuum= 1.4e-006
>> Magnet (steps)= 11572
>> When I select reference gas (CO2) on the conflo screen to do a jump
>> calibration no CO2 gas is flowing into the system. I checked for a leak
>> and NO
>> leak, we have a half tank CO2 gas. It seems ions are not reaching the cups
>> or
>> ions are not generated. I checked the CO2 tank is open, conflo is open and
>> SGE valve is open.
>> I am planning to remove the source again and see if the small opening in
>> the
>> side of the ion source chamber is somehow blocked or miss aligned (even
>> though I checked every thing before I put it back) . Or when I pushed the
>> source into the mass spectrometer possibly a wire may have been
>> disconnected?.
>> Any advice or suggestions before I remove the ion source again to check
>> for
>> any loose connection.
>> Thanks
>> Million