ORTEC Micro-Detective-HX, Руководство по эксплуатации

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5. MONITORING AND MEASURING WITH THE MICRO-DETECTIVE-HX
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Once you exit this screen, you can use the Replay feature to review the data from this
survey; see Chapter 6. You can also download this ICD1/ICD2 file pair to a PC (see
Chapter 7) and manipulate the files with tools such as the accompanying HX Online Analysis
Program.
If the End Survey report has multiple pages of results, the pages are entitled Survey 1 of [x],
Survey 2 of [x], etc., where x is the total number of pages of the report. Press or tap S to cycle
through the pages.
5.6. Example Survey and End Survey Report
In this example, we conduct a Detect mode survey for 5 minutes. To set up for this survey, we
have switched Na-22 and Y-88 from threat status to innocent (see Section 3.4.2.2).
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After 1 minute of surveying, we note elevated signal in both the Signal Index and SNM
Index strip charts, then an Am-241 threat (red) alarm is generated. This is illustrated in
Fig. 42. We press or tap the S (Select) button to acknowledge the alarm, then move away
from the Am-241 for a few seconds. When the activity (based on the rolling-window
analysis) drops below the alarm threshold, the red LED stops flashing, and the Am-241 ID
drops off the screen.
Unknown to us, there is also a weak Th-232 source nearby, but it is not strong enough to
trigger an ID and generate an alarm within any 8-second rolling window analysis.
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We stop to perform a 2-minute Long Sample to
locate the Am-241 source. During this Long Sample,
we detect the Am-241 and an innocent nuclide,
Na-22. The corresponding threat (red) and innocent
(green) alarms are generated. We press or tap the S
button twice to acknowledge the two alarms. How-
ever, we still do not detect the weak Th-232 source.
!
We resume surveying and, at minute 4, we find
a Y-88 source and another Na-22 source, both
of which post innocent (green) alarms. We press
or tap the S button twice to acknowledge the two
alarms, and then move far enough from any detect-
able sources that the Am-241, Y-88, and Na-22
identifications drop off the screen after a few seconds
and the screen background changes back to white.
We still do not detect Th-232.
Fig. 42. Signal and SNM
Indexes Track Am-241 Activity.