BNC 970 Portable Multi-Channel Analyzer (MCA) - Manual (Page 37)

Model 970 Instruction Manual 34
Immediately below the four buttons is a status display showing the current status of data
acquisition.
Moving downward, the next object is the white Time (sec) input box, with a checkbox immediately
to its left. If the checkbox is checked, the 970 will stop acquiring a spectrum when the total
counting time equals this value. Time units are in seconds. An Acquisition cannot be started or
continued if the checkbox is checked and the Acquisition time equals or exceeds the amount of
time in the input box. Typing in the Time (sec) box will immediately un-check it; pressing Enter on
the keyboard after changing the Time (sec) value will re-check it.
Directly underneath the Time (sec) input box are two displays. The first shows the total elapsed
Time in the data acquisition, and the second shows the Total number of Counts collected.
The next item down is the Dwell Time control. This determines how frequently data is posted on
the Chart, what period of time each data point represents, and the sum of time that each data
point represents. This value can be altered from 1 to 60 seconds. This control can be changed
while an Acquisition is in progress.
Below that is a box labeled Display Data as. The left axis Chart units can be changed between
counts (accumulated in each dwell time period), cpm or cps (averaged over the dwell time
period). This cannot be changed after an Acquisition has been started, or until the Chart is
cleared.
The next set of controls (Scroll Width) affect the bottom axis of the Chart display. If Scroll Width is
checked, then the width of the bottom axis will be the number of seconds displayed in the input
box immediately below. If Scroll Width is not checked, then the width of the bottom axis will reflect
all of the data points collected. Note that performance may suffer if a very large number of data
points (1500 or so) are displayed.
The controls in the next area are the Autosave features. If Autosave Every is checked, then the
accumulated data will be saved to sequential files at a frequency determined by the value in the
box immediately below. If Low Activity Sample is checked in the Utility Menu, you will be able to
choose whether to Autosave just the low activity data (i.e., only non-zero values) or both.