Guralp Systems CMG-DM24 User Manual
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Operator's guide
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Time synchronization to an attached GPS receiver or from a
remote time source.
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An ARM microprocessor, which formats and buffers data in an
on-board 256k RAM ring buffer.
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Efficient data storage and transmission using the Güralp
Compressed Format (GCF).
•
RS232 serial data output at user-selectable baud rates, with
automatic modem dial-out facility.
•
Built-in microprocessor system configuration and sensor
control, including locking and unlocking, centring and
calibration.
•
Low system power consumption.
•
Flash EEPROM for program code and filter coefficients.
•
High-impedance, low-noise, differential input pre-amplifier
modules with adjustable gain.
•
Internal electronic thermometer provides temperature
measurements at an accuracy up to ± 0.33 °C, with a linearity of
± 0.5 °C.
•
Optional Flash memory storage.
•
Optional IEEE 1394 FireWire interface, allowing you to
download GCF data directly onto a compatible disk by simply
plugging the disk into the FireWire connector inside the casing,
and monitoring progress on the built-in LCD screen.
•
Optional USB interface, enabling fast data transfer direct to a PC
or other recording device.
The DM24 can be connected to two Güralp analogue sensors, or up to
six conventional single-axis seismometers, through its SENSOR A and
SENSOR B connectors. (Single-sensor and integrated DM24 units have
only SENSOR A connectors). Signals from these sensors are digitized to
32-bit precision, initially at 2000 Hz. Data is output through the DATA
OUT serial port of the digitizer in the flexible GCF format, either to a
PC or a Güralp data module. Timing signals are gathered from a GPS
unit connected to the single GPS port.
October 2009
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