Canberra Lynx DSA, Руководство пользователя

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Baseline Restorer
Lynx DSA User's Manual - 9240227J 197
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Next, increase the FDisc Setting level until the ICR LED indicator is no
longer on continuously, but shows low activity by blinking green
occasionally. The fast discriminator threshold is properly set.
Note: With the Fast Discriminator in the manual mode, the threshold must be
rechecked and adjusted if the Detector/Preamplifier is changed or the Lynx’s
GAIN is changed.
Baseline Restorer
The digital baseline restorer in the Lynx is flexible and allows adjustment for varying
baseline conditions affected by detector type, noise and count rate. The baseline
restorer rate is selected using the BLR mode drop down menu in the Filter Device
Adjust screen.
With the Baseline set to AUTO, the digital baseline restorer is automatically set for
optimum performance throughout the usable input count rate range.
The restorer can also be set to three manual settings: SOFT MEDIUM and HARD.
These setting can be used to manually optimize the BLR response for a specific
detector and count rate application or system noise condition. The SOFT selection
significantly reduces the baseline restorer’s restoration rate. This may prove to be
advantageous in some low count rate/low energy applications. With the SOFT
selected, the restorer’s low frequency noise suppression effectiveness is reduced. The
ambient low frequency noise and the implementation of noise reduction techniques
regarding setup can easily be assessed and tested.
For situations where a higher than normal restoration rate is required, the restorer rate
may be set to MEDIUM or HARD, which increases restoration rate proportionately.
This can improve performance at extremely high input counting rates or where more
control is required to maintain the baseline, such as with some NaI(Tl) scintillation
detector systems or detectors which exhibit excessive microphonics.