Signal-to-noise reported as 0.00 for all samples in the TargetLynx summary - WKB51365

SYMPTOMS

• Signal-to-noise reported as 0.00 for all samples
• Found: Chrom Noise also reported as 0.00
• Found: Noise start and end times are both set to 0.00 in the TargetLynx method

ENVIRONMENT

• MassLynx 4.1
• TargetLynx 4.1

CAUSE

Too few points in the extracted noise trace to make a noise measurement

FIX or WORKAROUND

1. Enter a fixed time for the Noise Start and Noise End times in the TargetLynx method.
2. Reprocess the data.

ADDITIONAL INFORMATION

In TargetLynx, if the Noise Start and End times are both set to 0.00, this initiates an algorithm that extracts and plots just the peak in the traces that are not part of a chromatographic peak. Once the noise trace is plotted, the peak-to-peak (or RMS) noise measurement is made on those peaks. If the acquisition time for the MS function is closely defined around the chromatographic peak, there will not be enough points in the extracted noise chromatogram after the points for the peak have been discounted.