Guralp Systems CMG-CD24 - Manual (Page 65)

Operator's Guide
For example, 4 10 10 RATIOS will cause the CD24 to trigger if the
STA/LTA ratio is above 4 for the Z component, or above 10 for the
horizontal components.
5.5.6 BANDPASS
Syntax: tap filter BANDPASS
The CD24 passes the stream(s) which generate STA/LTA triggers
through a band-pass filter before examining them. This filtering does
not affect the continuous outputs. The corner frequency of the band-
pass filter can be changed with the BANDPASS command.
•
filter = 1 creates a filter with a corner at 10 % of the Nyquist
frequency for tap tap (i.e. 5 % of its sample rate)
•
filter = 2 creates a filter with a corner at 20 % of the Nyquist
frequency for tap tap (i.e. 15 % of its sample rate)
•
filter = 5 creates a filter with a corner at 50 % of the Nyquist
frequency for tap tap (i.e. 25 % of its sample rate)
5.5.7 MICROG
Syntax: level MICROG
Sets the output level above which a trigger will be declared when
using the LEVEL triggering algorithm. level is interpreted in counts.
To interpret in ground units use MICRO-G.
5.5.8 MICRO-G
Syntax: level MICRO-G
Sets the output level above which a trigger will be declared when
using the LEVEL triggering algorithm. level is interpreted in ground
units (
μg) if there is a correctly populated infoblock (calvals),
otherwise the level will be interpreted in counts (see MICROG).
5.5.9 HIGHPASS
Syntax: filter HIGHPASS
Instructs the digitiser to pass the stream(s) which generate LEVEL
triggers through a high-pass filter before examining them. filter can
be:
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