
Optimizing Instrument Settings Parameters
Voyager
™
Biospectrometry
™
Workstation User’s Guide 5-71
5
4. Continue increasing (or decreasing) the Delay Time in
100 nsec for Linear mode, or 50 nsec for Reflector mode
increments (or decrements) until optimum resolution is
obtained.
Hint: If you obtain close to acceptable resolution at one
setting, but less acceptable resolution at the next
setting, you may have adjusted the Delay Time too far.
Increase or decrease in smaller increments until you
obtain optimum resolution.
5. If resolution is still not optimized after you adjust the Delay
Time setting, adjust the Grid Voltage% as described in
Section 5.4.3.5, Optimizing Grid Voltage%. Reload the
standard .BIC file you started with, and use the Delay
Time value provided in the .BIC file.
6. If you are analyzing samples below 2,000 Da, you may be
able to improve resolution by adjusting the Accelerating
Voltage:
• Linear mode—Decrease from 20,000 V to
15,000 V to increase flight times.
• Reflector mode—Decrease to 15,000 V,
10,000 V, or 5,000 V. However, these lower
settings will compromise sensitivity.
7. Save the .BIC file.
Setting Delay
Time to resolve
isotopes across a
broad mass range
To resolve isotopes across a broad mass range, select a
Delay Time setting that yields optimum resolution at the higher
end of the mass range. Isotopes at lower masses can be
resolved at lower resolution. Selecting a Delay Time that
maximizes resolution at lower masses may not resolve
isotopes at higher masses.
When selecting a Delay Time to resolve isotopes across a
broad mass range, resolution and signal intensity at the lower
end of the mass range may be compromised, but you should
observe isotopic resolution across the entire mass range.
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