Canberra Lynx DSA, Руководство пользователя

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Chapter 5 Web-Based Operations
108 Lynx DSA User's Manual - 9240227J
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Automatic pole-zero adjustment will have an effect on the position of the
data within the spectrum so it is only available when acquisition is not in
progress.
Note: While the Auto Pole Zero procedure is operating, the Start/Stop acquisition
controls are disabled. While acquisition is in progress, the Start button for the
Auto Pole Zero is disabled.
An automatic pole-zero procedure is initiated by pressing the Start button. If the
Start button is 'grayed out', acquisition may be in progress. The automatic pole-zero
procedure will begin when Start button is pressed; the status will be reported as
“Progress”. The Auto P/Z procedure will continue until either conversion is achieved,
or the three-minute timeout expires, or until the Stop button is pressed; the reported
Auto Pole Zero Status will be updated accordingly.
If timeout is reached, the hardware will be restored to the original Pole Zero setting
when the Auto P/Z procedure was started. The status will report as “Off, Timed Out”.
Status with “Input rate too low” or “Input rate too high” indicates that the event data
does not meet the rate or amplitude requirements. If stopped prematurely the status
will report as “Off, Aborted”.
Timeouts may be due to incorrect count rate, improper signal amplitude,
incompatible time constant from the preamplifier/detector, or a poor quality
signal (example: significant periodic noise or secondary time constants) from the
preamplifier/detector. You may wish to monitor the filter output with the
oscilloscope for further investigation into the cause for a failed result.
If the automatic pole zero completes successfully the hardware will be updated with
the new Pole Zero setting; the status will report back as “Done, Complete”. The Auto
Pole Zero Value will display the new Pole/Zero setting.
LT Trim
Allows adjustment of the trapezoid pulse evolution time or 'dead time' to optimize
live time correction (LTC) performance. The adjustment range is 0 to 1000; the
default value of 500 provides good LTC performance for a wide range of
applications. Please refer to Live Time Correction With a Live Source on page 191 for
additional details on optimizing the LT Trim setting.
Overload Recovery Extension Time
Time in microseconds added to the default overload recovery when a cosmic event
overloads the preamplifier. The default recovery time in the Lynx is approximately
2.5x the shaping time (Rise + Flat Top). The value specified through the Overload
Recovery Extension Time ranges from 0 microseconds to 6,550 microseconds in
steps of 10 microseconds.