Guralp Systems CMG-DM24 - Manual (Page 120)

CMG-DM24
9 Digitizer specifications
Seismic channels Number 4 – 8
Format 32 bit
Inputs
Differential with transient
protection; ±10 V input
range
Input impedance 1 MΩ, 10 nF
Common mode
rejection ratio
110 dB at 10 Hz
Mux channels Number 8
Format 24 bit
Inputs
Single ended; ±10 V
input range
GPS Unit External GPS (CMGGPS2)
Power
supplied through GPS
connector
Time format NMEA
Max. cable length 50 m
Sensor control Functions available
Lock, unlock and centre
sensor (active low
CMOS); enable
calibration
Sensor calibration Types
Sine and square wave;
adjustable amplitude and
frequency
Digital signal
processing
Type Texas TMS320CV33
Hardware sampling
rate
2 KHz
Sample output rates
6 cascaded rates, each 2,
4, or 5 times lower than
the previous rate (even
integers only)
Anti-aliasing filters 2 pole
Low-pass filters FIR
Out-of-band rejection 140 dB
In-band ripple –140 dB
120 Issue N