ORTEC DSPEC 50, Руководство пользователя по оборудованию

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DSPEC 50
®
and DSPEC 502
®
Digital Gamma-Ray Spectrometer User’s Manual 932502G / 0618
Figure 1. Demonstration of the DSPEC 50's Minimum and Maximum
Protection Times in Enhanced Throughput Mode. At the maximum
protection-time setting, the DSPEC 50 processes pulses in the
conventional way.
1.4. Enhanced Throughput Mode
To optimally process an input pulse stream, and thereby obtain the best spectral resolution, the
signal processing device should allow the input signal to return to baseline before beginning to
process the subsequent pulse. However, in cases where some loss of resolution is acceptable, it
is possible for a DSP to begin processing a subsequent pulse before the first pulse has returned
to the baseline,
provided the first pulse has returned to baseline when the peak-detect of the
second pulse occurs .
The ORTEC Enhanced Throughput Mode takes advantage of this feature of digital signal pro-
cessing by allowing you to adjust the delay between the peak-detect and the start of processing
of the next pulse. The dead time for a conventionally processed pulse is the sum of the pulse’s
rise time, flattop, and fall time. By contrast, the dead time in ORTEC’s Enhanced Throughput
Mode can be as little as the rise time plus the flattop. These two scenarios are illustrated in
Fig. 1. The DSPEC 50 lets you set a
protection time (PT), following a peak-detect, that blocks
subsequent peak-detects until the protection time has elapsed. Note that the conventional dead
time illustrated in Fig. 1 is the same as the maximum protection time in Enhanced Through-
put Mode.
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