Guralp Systems Scream User Manual
Page 69

User guide
parameters will be appropriate and the system should rapidly switch
to the ‘fine’ control mode. The system reports its control status and
parameters each minute, with error measurements given in nominal
timebase units. In a stable temperature environment, the system
should soon settle down showing an offset error of only a few
thousand (average error < 100 microseconds) and a drift rate under
100 counts (< 1 in 10
-6
).
6.2.2 Graphing status information
Newer Güralp digitisers output a status block every few minutes giving
information about the GPS status, ambient temperature, etc:
Scream! can automatically extract measurements from these messages
and show them in graphical form. For each field Scream! finds, a
check-box is displayed at the top of the Status window. In the
example above, Scream! has found Offset, Drift, PWM, Volts (i.e. user
input) and Temp (temperature) fields in the status messages. Not all
digitisers output all of these fields, so some of these check-boxes may
not be present.
To display any or all of these fields in graphical form, tick the
check-box(es) for the field(s) you want to examine:
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