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jessejoe
Feb 12, 2009, 10:49 AM
I am working with the validation of an HP-5890 with FID detector. Everything has been coming fine, I am new on this and I really do not know how to interpret my noise test, I have found some specifications for 6890 series (noise 0.038 pA), but not for 5890 series, my chromatograms show results of area units in counts and being honest I do not know how to convert this units to pA and see if my is in spec or not.

Please excuse my ignorance about and please help me, It is very important to me!!

Thanks in advance,

rwinterton
Feb 12, 2009, 02:22 PM
The noise is 0.038 picoamps. That's the noise on the signal coming from the FID detector. I'm not sure you can convert the units in counts to pA unless you know some more about the A/D converter (analog to digital converter). Of course, the 0.038 pA is undoubtedly converted to a voltage by passing it through a resistor of some value.

If you had some sort of idea about the magnitude of some standard signal (in pA) coming from the detector, you could ratio it to the noise and make sure the signal-to-noise ratio is adequate.

Maybe someone else can add some insight to this. I've used an HP-5890, but I never had to do this kind of analysis.