dimtel
dimtel
5.3
Display Panels
Figure 16: General-purpose I/O panel: front/back-end driver
buttons. Depending on which zero crossing the phase shifter is centered dif-
ferent loop polarities need to be selected using LOOP SIGN. LOOP GAIN
parameter must be adjusted to optimize the loop response in terms of noise,
bandwidth, and overshoot. Typically the optimization can be carried out
with beam by stepping the input offset and observing the phase servo re-
sponse using a stripchart tool. INPUT OFFSET is used to zero out possible
mixer offset or, alternatively, to introduce an offset. Such an offset is typically
used when the beam loading transient is highly asymmetric to avoid reaching
ADC saturation prematurely. SATURATION LIMIT parameter defines the
maximum deviation from the phase setpoint that can be introduced by the
phase servo. This limit must be set below
π/
2 to make sure the phase servo
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