BNC 971 Food-SSAFE Analysis Kit - Manual (Page 7)

Food-SSAFE Operation Manual Page 8 of 20
Basic Functions of the Main Screen
The Main Screen is divided into three sections. The top
section (colored blue by default) is the Spectrum Display.
a. Colors for the background and spectrum trace (as well
as for other items) can be changed using
View|Preferences.
b. Tapping the Spectrum Display will cause a line to be
displayed at the tapped location. The channel number
and number of counts in that channel will be
displayed. If an energy calibration has been
performed the energy (in keV) will also be displayed.
Tapping in the area beneath the Spectrum Display
will hide the line. Alternately, use View|View
Preferences to set a timed line display where the line
will be hidden after a set number of seconds.
c. An MODEL 970 spectrum (4096 channels) contains
more data than can be displayed, as the PPC screen is
only 240 pixels wide. This means that in normal
(Full Screen) mode, each screen pixel represents the
sum of about 17 channels. To view a section of the
spectrum in the greatest detail (one channel per pixel)
select View|Zoom. If the Spectrum Display has been
tapped the zoomed display will be centered on the
tapped channel. When zoomed, using the scroll bar
on the top of the zoomed display can move the
section being viewed. The display will automatically
scale to the channel with the greatest number of
counts in the displayed region. Return to the normal
view by tapping View|Zoom again to uncheck the item.
d. The spectrum display can also be smoothed by
selecting View|Smoothed Spectrum. Select
View|Smoothed Spectrum again to uncheck the item
and go back to the raw data display.
e. The lower area (gray background by default) contains
information about the current MODEL 970 and
detector as well as sample acquisition information.
The top line contains the total number of counts in the
entire spectrum. The second line is the total elapsed
spectrum acquisition time. The third line is the count
rate (in cpm) from about the most recent 20 seconds
of the acquisition. The fourth, fifth, and sixth lines
contain the MODEL 970 serial number, the detector