Rawdata File; Peak Detector - Agilent Technologies 1100 Series Reference Manual

continuous, linear scale, an interpolation algorithm is applied. This algorithm
uses a wavelength calibration table and actual wavelength data, derived from
the deuterium emission lines at 486 nm and 656 nm.
Wavelength calibration is done for each individual spectrograph during the
production process. The individual calibration coefficients are stored in the
wavelength calibration table in an EEPROM (electrically erasable PROM),
which is part of the spectrograph electronics. Actually two sets of coefficients
are used, one set for the wavelength range below the second order filter,
located on the photodiode array, and one set for the upper wavelength range.
During each start-up of the spectrophotometer, each discrete wavelength
value is assigned a photodiode of the array.
Recalibration in the diagnostic section of your Agilent ChemStation software
can be performed to compensate for minor deviations from initial production
conditions. Recalibration is achieved using the deuterium line data, that is, the
exact positions of the deuterium emission lines at 486 nm and 656 nm. With
the user interface, the operator can include the new parameters in the
wavelength calibration table to calculate a table of correction coefficients
which are applied to each spectrum.

Rawdata File

The runbuffer within the detector is used for signal and spectra data only. If
the runbuffer is full, no further signal data are entered. This will guarantee
useful signal data but may cause loss of interesting spectral data. The
runbuffer can hold about 90 spectra depending on the settings and may be
expanded by additional memory on the detector main board (SIMM modules).

Peak Detector

The peak detector (PD) always uses signal A as the pilot signal. The PD is
adjusted by means of two setpoints: peakwidth and threshold. Both setpoints
are time-programmable. While the PD-threshold is a method parameter of its
own, the PD-peakwidth parameter is derived from the general peakwidth
(PKWD) parameter. At the start of the run, the value for the PD-peakwidth is
set equal to the PKWD setpoint. The peak detector recognizes changes in the
1100 Series DAD and MWD Reference Manual
Introduction to the Detector 6
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