Dear Dominique,
Are those Finnigan people paid for hours ? If so, you better buy a 
solid state magnet and scan your mass spectrum with high voltage... 
The described drawback does not seem to be extremely serious - most 
probably the electromagnet current stabilizer does not receive a 
stable reference signal while interfaced to the DA converter in a 
computer. That is why all is OK in the manual mode. 
Let the Finnigans work for a couple of days and then 
build your own interface.
With regards,


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Tomasz Durakiewicz
Mass Spectrometry Lab, Institute of Physics
Maria Curie-Sklodowska University, Lublin, POLAND
tel. (0-81) 37 61 78, fax (0-81) 33 669
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