How-to guides
Information to help you get more out of your Güralp installation.
General topics
Troubleshooting DM24 mk3 digitizers
Common problems with newer Güralp Systems DM24 units, and how to solve them.
Troubleshooting DM24 mk2 digitizers
Common problems with older Güralp Systems DM24 units, and how to solve them.
Calibration with a broadband noise source
How to use the DM24mk3's pseudo-random broadband noise generator to calibrate the whole pass band of a sensor in one experiment.
Calibration with a square wave (step) signal
How to calibrate sensors using a step signal generated by a DM24.
Calibration with a sine wave signal
How to calibrate sensors using a sine wave generated by a DM24, or by your own equipment through a Handheld Control Unit.
Information blocks from Güralp digitizers
How to create and interpret the calibration information block stored in a CMG-DM24 or other Güralp digital instrument.
Troubleshooting DCM installations
Common problems with Data Communications Modules, and how to solve them.
Scream! features
Using infoblocks with Scream!
How to upload and download the information block held in a CMG-DM24 or other Güralp digital instrument.
Determining sensor orientation
A MATLAB extension to Scream! can calculate the orientation of a borehole sensor by correlating signals with those measured at a reference instrument.
Units and scaling in Scream!
Scream! lets you scale streams in several different ways. This how-to explains the differences between them.
Exploring the frequency domain in Scream!
March 2006How to use the filtering features of Scream! 4.3 to study different types of seismic event.
Running simultaneous Scream! instances
How to set up your computer to run several copies of Scream! at once, with different configurations.
Technical matters
Using GCF data in third party software
How to convert GCF files and streams into other seismic data formats.
Güralp Compressed Format (GCF) Specifications
The full specification of the formats and protocolos used by Güralp digitizers and data modules.
Expressing response information in SEED files
Constructing SEED headers containing calibration information for Güralp instruments.
FIR filter configuration of older CMG-6TD instruments
Filters used by older (non-CD24) 6TD instruments.
FIR filter configuration of the CMG-CD24
Filters used in newer CMG-CD24 and CMG-EDU systems (those based on the CMG-CD24 compact digitizer.)
Determining FIR filter information from GCF data
GCF data blocks include a code describing the sequence of FIR filters used inside the digitizer to generate the data.
Poles and zeroes with positive normalization factors
Some seismology software will not accept the poles and zeroes determined by our calibration procedure. These calculated values should be used if you have problems.
Güralp Compressed Format (GCF) Quick Reference
A quick reference guide to the format used by Güralp digitizers and data modules.