Yeah, we had troubles like this when we first started up our 
instrument. It turned out that one of the resistances was entered 
incorrectly (off by an order of magnitude) in Configurator. Once we 
got the exponent right, we got great H3+ results.

~Penny

At 06:21 PM 11/29/2007, you wrote:
>Hi Stan--
>
>Double check the cup configuration and make sure you have the right 
>amplification values in the right cups.
>
>take care
>
>gerry
>
>Stan Klonowski wrote:
>>Esteemed isotope experts,
>>
>>I have run out of ideas. I recently had to reinstall isodat and 
>>have gotten everything up and running fine fine except I cannot get 
>>what is a reasonable H3+ correction.  The lowest I can get is 155. 
>>Well the lowest I can get is whatever value I overwrite in the 
>>method plus 155. If I start from nothing I will get a value of 5348 
>>ppm/nA.  Everything is the same as before: peak shapes look great 
>>varying tuning set ups seems to matter very little.
>>
>>I am stumped what am I missing?
>>
>>Instrument details: Mat 253/isodat with latest sp, conflo for the inlet.
>>
>>Stan Klonowski

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                       Dr. Pennilyn Higgins
                        Research Associate

                             "SIREAL"
   Stable Isotope Ratios in the Environment Analytical Laboratory

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