Guralp Systems CMG-3ESPCD User Manual
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CMG-3ESPCD Digital Broadband Seismometer
Using Scream!
Type you set here determines which functions will be available
through the Scream! digitiser configuration set-up interface or through
interactive commands. The correct value for your 3ESPCD is
“CMG3T / ESPC”
•
GPS Type : The digitiser 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
digitiser expects to receive two-byte packets from the central timing
source, which may have its own GPS unit, or take signals from one of
the radio time standards. Choose the mode you require from the
drop-down menu.
•
Enable GPS power cycling : If you are using a GPS unit to receive time
signals, but do not experience significant drift in the system's clock (for
example, in a stable-temperature environment), you can save power by
selecting Enable GPS power cycling. With this option in use, the GPS
time is only checked at intervals of a specified number of hours.
Disabling this option keeps the GPS unit running constantly; if you
have ample power, this will give the most accurate results. You can
choose any whole number of hours for the interval.
5.1.2 Output control
The Output control tab allows you to configure which data streams are sent to
Scream! from the digitiser.
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Issue B - November 2013