HP (Hewlett-Packard) 4 Series Calculator User Manual


 
Using the Signal-to-Noise Ratio Calculator
Data Explorer
Software Users Guide 6-23
6
6.4 Using the Signal-to-Noise Ratio
Calculator
Description A signal-to-noise ratio is typically used to describe how well a
peak of interest in a spectrum or chromatogram is
distinguished from background noise.
The Data Explorer software provides two signal-to-noise ratio
methods that calculate signal-to-RMS noise (electronic and
chemical):
AutoYou specify the peak for calculation and the
software automatically calculates the average noise
across the spectrum.
ManualYou specify the peak and the baseline region
for calculation. For accurate results, this method requires
a flat (non-rising) baseline that does not include peaks.
The manual method is useful when evaluating a narrow
region around a peak to determine the relative
significance of a peak.
Calculating
signal-to-noise
ratio
To calculate a signal-to-noise ratio:
1. Click the Spectrum window to activate it.
2. From the Tools menu, select S/N Calculator.
The Signal-to-Noise Calculator dialog box (Figure 6-14)
is displayed.
Figure 6-14 Signal-to-Noise Dialog Box