Guralp Systems CMG-CD24 - Manual (Page 27)

Operator's Guide
generated by the digitiser 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 digitiser’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, while the serial number cannot be longer than 4.
Sensor Type : This option tells Scream! which control commands to
make available to the user. The CD24 does not require separate
control commands, so you should not change this option.
GPS Type : The digitiser needs to be able to time-stamp accurately all
data that passes through it. It sets its clock by receiving time signals
from the GPS satellite network using an attached Trimble GPS unit.
This is hard-wired into the CD24, so the GPS Type setting has no
effect.
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.
3.1.2 Output control
The Output control tab allows you to select which data streams are sent
to Scream! from the digitiser.
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