Guralp Systems CMG-DM24 - Manual (Page 38)

CMG-DM24
For example, setting the STA to 1 second, the LTA to 10 seconds and
the Ratio to 4 would give rise to the following trigger behaviour:
Usually, the values of the STA and LTA periods, and of the Ratio, will
be the same for all checked channels. For convenience, Scream! will
automatically fill in other values to match ones you enter. If you want
to use different values for some channels, you should un-check the
Common values box before altering them.
Once you have enabled the STA/LTA triggering method on a particular
channel, you can use the Control window to change the values of the
38 Issue N