CMG-DM24

CMG-DM24

The CMG-DM24 is a high-quality digitizer module with full 24-bit resolution, designed for data quality and durability. Both 3- and 6-component models are available.

Features

• 3 or 6 low noise 24-bit ADCs
• Additional full-rate data channel for user signals and calibration
• Low power 32-bit DSP and ARM processor (<1 W recording 4 channels at 100 samples/s)
• Multiple concurrent data rates up to 1000 samples/s
• STA/LTA ratio, level, external and software triggering
• UTC timestamped data from attached GPS receiver
• 8 environmental channels with 20-bit resolution (3 × mass position, temperature, 4 × user)
• Full control of Güralp broadband seismometers
• Calibration using step, sinusoid or pseudo-random broadband noise signals
• 64 Mb Flash memory with fast FireWire data transfer
• Fully configurable using Güralp data modules and software

Options

• Extended Flash memory up to 8 Gb
• 8 additional environmental channels
• Further full-rate channels available using daisy-chaining
• Ultra-low noise option at a small cost in power
• Borehole form factor
• Integrated module form factor can be retrofitted to existing sensors (3T to 3TD, 40T to 40TD)
• CMG-DM24S3DCM all-in-one digitizer, data logger, serial output device and network data centre
• CMG-DM24S12AMS strong-motion acquisition system
• LCD state-of-health display
• FireWire interface for external storage devices
• USB memory stick interface (case lid can be closed with memory stick in place)

CMG-DM24mk3 with both optional LCD display and optional FireWire interface

Performance

Performance of the standard CMG-DM24.

Performance of the low noise CMG-DM24 option.

The CMG-24 uses the latest 24-bit ADC technology to provide multiple concurrent sample rates from 1000 samples/s down to 1 sample/s. The DSP chip set and digitizer design give the DM24 a first-class noise profile. Input-terminated noise tests demonstrate that the performance of the DM24 at 40 samples/s exceeds 22.5 bits, giving it a maximum potential dynamic range of over 137 dB. The noise floor is further reduced to over 24 bits at slower sample rates.

The low noise variant of the DM24 has a maximum potential dynamic range over 141 dB, exceeding 23 bits of resolution at 40 samples/s. To take advantage of this resolution, the output word length is increased to 32 bits. The low noise variant draws slightly more power than the standard model owing to the increased processing required.

CMG-DM24 news