Guralp Systems CMG-DM24 - Manual (Page 31)

Operator's guide
System ID
The System ID pane gives information about the digitizer and its
internal software, and allows you to change GPS timing parameters.
System Identifier and Serial Number : The digitizer type is identified by
its system identifier and serial number. Every data and status block
generated by the digitizer includes these two fields at the beginning, so
that the block’s origin can be identified. On delivery from the factory,
the system identifier and the serial number are set to the GSL works
order number and the digitizer’s serial number, but any combination
of letters A-Z and numbers can be used, such as an abbreviation of
your institution’s name, etc. The system identifier can be up to 5
characters long, whilst the serial number cannot be longer than 4.
Sensor Type : If the sensor attached to the digitizer is a Güralp velocity
sensor, useful seismometer functions (such as sensor locking, centring,
and calibration) may be controlled through the digitizer. The Sensor
Type you set here determines which functions will be available
through the Scream! digitizer configuration set-up interface or through
interactive commands.
GPS Type : The digitizer needs to be able to time-stamp accurately all
data that passes through it. It can set its clock either by receiving time
signals from the GPS satellite network using an attached Garmin-
compatible (NMEA output) unit, or by taking time information from a
central site (stream sync mode). In stream sync mode, the digitizer
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