Zero Ratio
The Zero ratio value is interpreted by the stabilizer as the ratio to maintain between the
two zero windows (ratio = upper window / lower window). For instance, a value of 1
would be appropriate for a pure Gaussian peak.
DSP Gain Parameters
The DSP Gain settings screen (Figure 12) for the 9660 contains the following controls.
Coarse Gain
Sets the device’s coarse gain. It’s best to choose the highest Coarse Gain which, com-
bined with the Fine and Super-Fine Gains, will produce the total desired gain.
Fine Gain
Sets the device’s Fine Gain multiplier.
S-Fine Gain
Sets the device’s Super-Fine Gain multiplier.
The combination of Coarse and Fine Gain sets the overall system gain to match the re-
quirements of the detector and energy application; overall gain is continuously vari-
able from x2.0 to x1,536. The Fine Gain factor is dependent on the Super Fine Gain
(SFG) value. With the SFG set to 0.0000e
-2
, the Fine Gain covers a range of x0.4 to
x1.6. The SFG value adds to the Fine Gain factor and covers a range of 0.0000e
-2
to
3.0000e
-2
.
Offset
Sets the devices digital offset in channels. The digital offset shifts the memory assign-
ment of the device’s conversions to the left (e.g. an offset value of 4096 would shift
channel 4096 down to correspond to channel zero of the memory).
Chapter 3 - Genie™ 2000 User Interface and Controls
16
Model 9660-9660A ICB Digital Signal Processor
Figure 12 Adjust Screen's Gain Settings