Table 3 - GEOS parameters for typical deployment and sensor parameters

Channel 1,2,3 (+ signal) = Up, North, East acceleration (FBA13)
Channel 4,5,6 (+ signal) = Up, North, East velocity (L22D)
Digitizing constant = 3276.8 count/volt
Sample Rate = 200 samples/second/channel
Trigger channel = 4
Window for short-term average = 0.2 - 0.8 second
Window for long-term average = 5 - 20 second
Trigger ratio (sta/lta) = 8:1 or 16:1
Pre-event signal duration ‰ 2 second
Record duration ‰ 10 - 40 second
Anti-alias filter corner frequency = 50 Hz
Anti-alias filter rolloff above corner = 42 dB/octave
     Sensor         Serial #   Parameters

Standard sensors:
     FBA13          all*       "Nat freq" ‰ 50 Hz, Sens ‰ 0.0051 V/cm/s2
     L22D           all*       Nat freq ‰ 2 Hz, Dmp ‰ 0.7 critical, Sens ‰ 0.5 V/cm/s

Other sensors:
     L4C            all*       Nat freq ‰ 1 Hz, Dmp ‰ 0.7 critical, Sens ‰ 1.0 V/cm/s
     Guralp CMG4    4016       Sens = 0.560 V/m/s2
     "              4017       Sens = 0.560 V/m/s2
     "              4031       Sens = 0.576 V/m/s2
     "              4032       Sens = 0.576 V/m/s2
     Guralp CMG5    7-Comp1    Sens = 0.556 V/m/s2
     "              7-Comp2    Sens = 0.577 V/m/s2
     "              7-Comp3    Sens = 0.570 V/m/s2
     Teledyne HS10  Prototype  Nat freq = 1.0 Hz, Dmp = 0.7 critical, Sens = 1.0 V/cm/s

* Calibration data available
U.S. Geological Survey

Open-File Report 90-503

Digital Recordings of Aftershocks of the
17 October 1989 Loma Prieta, California, Earthquake