Chapter 6 Using Tools and Applications

6

3.

Select the method to use, then right-click-drag on peaks

 

in the trace to enter the associated values displayed for

 

 

 

 

the method you select:

 

 

 

• Auto— Right-click-drag across the apex of the

 

 

 

peak for signal-to-noise calculation. The

 

 

 

software automatically calculates the average

 

 

 

 

 

noise across the entire spectrum.

 

 

 

The noise calculation is not affected by the

 

 

 

presence of peaks or a poor baseline.

 

 

 

• Manual— Right-click-drag across the apex of

 

 

 

the peak for signal-to-noise calculation.

 

 

 

Right-click-drag across a flat region of the

 

 

 

baseline to use to determine the RMS noise

 

 

 

for the calculation.

 

 

 

 

 

 

 

NOTE: If you enter a baseline value instead of

 

 

 

right-click-dragging, the software uses an RMS

 

 

 

value of 1.000 to perform the signal-to-noise

 

 

 

calculation.

 

 

 

 

 

4.

Click OK. The result is displayed in the Output window.

6-24 Applied Biosystems