How-to guides

Information to help you get more out of your Güralp installation.

General topics

Securing your systems

Physical and data security for seismic installations and networks.

Troubleshooting DCM installations

Common problems with Data Communications Modules, and how to solve them.

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.

Minimizing sensor offsets

Different ways of zeroing seismic instruments, and their effects.

Information blocks from Güralp digitizers

How to create and interpret the calibration information block stored in a CMG-DM24 or other Güralp digital instrument.

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 2006

How 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-DM24 mk3

Filters used by newer DM24 digitizers.

FIR filter configuration of the CMG-DM24 mk2

Filters used by older DM24 digitizers.

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.

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