Using Scream!
5 Using Scream!
Scream! is a versatile seismic data visualisation program for Güralp instruments
which runs on Windows and Linux computers. If a DM24's
DATA OUT
port is
connected to an RS232 port on a computer running Scream!, the program can be used
to analyze digitized data from the DM24's connected analogue sensors, and to
control/configure both the digitiser and the sensors themselves. Scream can also
work with network-attached digitisers.
Scream! is available for free download from Güralp Systems, or may have been
supplied with your equipment.
5.1 Configuring digitisers
Scream! distinguishes between
configuration
and
control
of digitisers. The most
important difference is that a digitiser may be
controlled
through Scream! at any
time whilst it is acquiring data, whereas
configuration
options only take effect after a
reboot (with consequent loss of data).
To change the configuration of any connected digitiser:
1. Locate the digitiser you want to configure. All connected digitisers have an
entry in the tree on the left of Scream!'s main window. If the digitiser is
transmitting data through a remote server, EAM or NAM, you may need to
“unroll” the entry for that server (by clicking on the icon) to see the
digitisers connected to it.
2. Right-click on the digitiser's icon ( ).
3. Click
Configure…
. Scream! will then contact the digitiser and retrieve its
current configuration, a process which will take a few seconds. This done, the
Configuration setup
window will be displayed.
4. Once you are happy with any changes you have made in the
Configuration
Setup
window, click
UPLOAD
to send them to the digitiser and reboot. This
will take a short while.
To control a digitiser whilst it is running, either right-click on the digitiser's entry in
the list and click
Control…
, or double-click the entry. In either case Scream! will
contact the digitiser to retrieve control information and display the
Control
window.
The options you can control immediately are:
•
the type of sensor you are using;
•
GPS power cycling options;
•
the short-term and long-term average values for triggering (but
not
which
streams perform the trigger, or which are output by it);
•
the length of pre-trigger and post-trigger periods;
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Issue U - December, 2021