I have been having a problem with the Mass Calibration program on my Delta
E running with isodat.  I want to recalibrate the mass scale.  The mass
scan runs, and finds the peaks. Then after entering Calibrate CO2, the
masses are assigned to the peaks.  THis is where the problem lies.  Mass 12
is assigned to  bdac setting of 298 (that's ok) and mass 44 to bdac 1008
(thats good too), but mass 28 is assigned to a bdac of 0 (zero).  I have
printed out the peak table and typed in the peaks and masses again keeping
the same values for 12 and 44 and assigning 28 to the peak at 700.  The
program won't accept it (it says someting like "data incorrect") and asks
me to do it again.  I have tried numerous runs and  have reloaded the
software but with the same result each time.  I have also tried various
combinations of peaks and masses.
Has anyone encountered this problem??  Any suggestions??

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Dr. Andrew R. Campbell                       *
Professor of Geology                         *
Dept. of Earth and Environmental Science     *
New Mexico Tech                              *
Socorro NM 87801                             *
Phone: 505-835-5327                          *
Fax:   505-835-6436                          *
e-mail: [log in to unmask]            *
www.ees.nmt.edu                              *
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