Hardware Recording - Syscom Video MR3000C User Manual

STA/LTA is a trigger algorithm usually used in the field of weak-motion seismology. The STA/LTA
continuously calculates the average values of the absolute amplitude of a seismic signal in two
consecutive moving-time windows. The short time window (STA) is sensitive to seismic events
while the long time window (LTA) provides information about the temporal amplitude of seismic
noise at the site. When the ratio of both exceeds a predefined value, the trigger is activated and an
event is recorded.
Figure 4.1.5. Trigger recording interface, in case of selection of STA/LTA as trigger mode.
4.1.3

Hardware recording

This section is dedicated only to MR3000TR.
In case of MR3000TR, an additional section is present regarding the settings for the hardware
trigger, since the instrument can be triggered via hardware, by using an external input.
The input must be a digital hardware trigger. The user should short the signal Trigger and GND to
start a trigger (consider the datasheet of the MR3000TR and the application note on the Alarm box
at the following web page
not to apply any input voltage on the trigger signal, in order not to damage it.
In this section, the user can set the pre-trigger, the post-trigger and the maximum duration,
analogously to the section 4.1.2.
MR3000CMR3000C_TR_v2.0_rev1.odt
http://www.syscom.ch/products/mr3000tr/
subject to technical change without notice
as reference). It is important
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