Digitizer that we used in Passive Seismic Tomography

Motto:

Common sense…uncommon innovation

Digitizer

External Hard Disk

FEATURES

•  24-bit delta sigma A/D converter, 4th generation seismic recorder  
•  3 or 6 channels
•  Events only telemetry available
•  Earthworm exporter

The SMART Series of instruments represent the logical solution for seismological data acquisition: a common design for a digitizer, portable recorder, and strong motion recorder

(the all-in-one solution).

The traditional difference between these instruments vanishes, a strong motion recorder can now simultaneously record continuously weak motion data on a large selection of media: up to 120 GB hard disks, Compact Flash memory, etc. All units are telemetry ready using the CD1.1 protocol.

Very low power consumption is supplemented by a complete set of serial and Ethernet communication ports. Theremovable hot-swappable enclosure has a USB2.0 port for very fast data download. A SEEDLink plug-in is also provided.

SMART-24 SERIES SPECIFICATIONS

DATA ACQUISITION

• Number of inputs 3 or 6 channels 
• Input type Balanced differential with transient protection suitable for both passive and active sensors
• Input range 5Vp-p, 20Vp-p and 40Vp-p bipolar differential, 2x1 Mohm
• Gain Software selectable: x1, x2, x4, x8, x16, x32, x64
• Common mode rejection Greater than 90 dB
• Digitizer Over sampled 24-bit Delta Sigma ADC with digital signal processing, 1 per channel
• Anti-alias filter Brickwall digital FIR filter, cutoff at 80% of and 130 dB down at output Nyquist frequency. Causal filter optional.
• Dynamic range Up to 138 dB
• Intermodulation distortion Less than –110 dB
• Sample rates 1, 5, 10, 20, 40, 50, 100, 125, 200, 250, 500, 1000, 2000 sps primary sample rates
• Noise ~1 count RMS at up to 200 sps

ACQUISITION MODES (SMART-24R® only)

• Continuous User selected start time, ring buffer or until storage full
• Timed 16 user programmable
• recording windows
• Triggered Threshold, STA/LTA (updating or non-updating), and external
• Pre-event length Up to 32,768 data samples
• Post-event length Up to remaining data storage
• DATA STORAGE (SMART-24R® only)
• On board memory 192 MB
• Type Up to 120 GB hard disk, up to 64 GB industrial grade Compact Flash memory, subject to market availability
• Recording format Standard FAT32 file system, drives readable directly on a PC, format converters available for 32-bit SUDS, SAC, SEG-Y, SEISAN, MatLab, miniSEED, CSS3.0 and SEED

INTERNAL RECORDING (ALL VERSIONS)

• Two PC Card slots for Compact Flash or microdrives, having 1 or 2 partitions and accessible by any ftp client.
• TIMING Voltage controlled TCXO with optional external GPS synch.
• Accuracy <10 microseconds of UTC with GPS lock
• Stability 0.5 PPM (when unlocked)
• GPS duty cycle User programmable GPS power on/off cycle times

INTERFACES

• Indicators Large graphic LCD, protected
• Communications 2xRS232, Ethernet, USB2.0 for the removable enclosure
• GPS Dedicated RS-422 serial port
• Power Main power and external battery
• Other I/O 5 or 8 12-bit analog inputs, external trigger in/out, 1 PPS in/out
• Calibration Pulse, sine wave, white noise, random binary, step functions, and shorted input
• Telemetry - CD1.1 protocol, 4 independent profiles to 4 different IP servers;
• - 64MB internal buffer for backfill;
• - continuous, events only or both

POWER

• Input 10 to 16 VDC
• Power consumption ~1 watt average (3 channels @ 100 sps and GPS power cycling)

PHYSICAL

• Construction Portable rugged molded case or extruded aluminum, all IP67
• Size 4.1 in (105 mm) w x 10.35 in (263 mm) l x 13.65 in (347 mm)
• Weight (24D only) 8.5 lbs (3.9 kg)
• Operating temperature -20C to +70C
• Humidity 0 to 100% (IP67)

Product by:

10755 SANDEN DRIVE, DALLAS, TEXAS 75238-1336

Phone: 214-221-0000 Fax: 214-343-4400

email: info@geoinstr.com Web: www.geoinstr.com