Guralp Systems CMG-CD24 - Manual (Page 35)

Operator's Guide
an internal buffer of some seconds which allows these data to be
added to the triggered stream. Pre-trigger data are particularly useful
for emergent-type signals, where the system does not trigger until one
phase after the first arrival. In addition, to ensure that the coda of each
event is included, some seconds of data are recorded after the trigger
condition has ended.
The two boxes at bottom right of the Triggering pane allow the user to
set the pre-trigger and post-trigger data intervals, in seconds. These
values determine the minimum length of time during which data will
be saved before the trigger condition occurs, and after it has lapsed.
Regardless of the intervals chosen, the data in the triggered streams
will begin on a whole second.
3.1.4 Mux channels
The CD24 provides a range of slow-rate auxiliary channels for
reporting the system's state of health and other diagnostic information,
known as multiplexed (“Mux”) channels. The number of Mux
channels depends on the model and configuration of your digitiser.
Generally, three channels are used to report the sensor mass position,
and another measures the internal temperature of the digitiser. In
addition to these, up to 12 Mux channels may be supplied for the
user's own purposes. Some digitisers have a separate AUXILIARY port
which can be used as input for these channels.
The collection and transmission of Mux channels is controlled using
the Mux Channels pane:
If a tick is placed in the box next to a channel, its data will be collected
and transmitted as a data stream in GCF format, just as with the
normal data channels. To indicate that the data come from a Mux
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