This is program DISPCAL, version 8, April 2008 calibration of a Mark L4-3D on the Lennartz step table Data File: Potsdam09\steptable1.s Seismometer: L4-3D #2862 Parameters read from file dispotstep.par: ts0= 0.94 hs0=0.637 volts= 1.000 displ= 0.884 gap=0.350 Butterworth low-pass filter To= 0.00 s Correction factor (source+load)/load = 1.000 Parameters set in the source code: ndim= 480000 npol=3 header: data\pri1 reading 4000 samples from file Potsdam09\steptable1.s writing 4000 samples into file dispcal.dat conversion to ground velocity removing polynomial trend measuring curvature of the velocity trace writing 4000 samples into file dispcal.str Quiet intervals: min. length 0.35 s, max. 1.75 s evaluated Threshold for quiet intervals set at 4006.570 counts removing polynomial vel. trend determined from quiet intervals writing 4000 samples into file dispcal.vel locating pulses of velocity (steps of displacement) ============ 9 pulses found. ============ removing hypothetical baseline from velocity trace integrating "cleaned" velocity to displacement writing 4000 samples into file dispcal.dis measuring the steps of displacement preparing the residual displacement for display writing 4000 samples into file dispcal.res Raw average abs. step: 161778.042 +- 3361.455 counts rms Raw avg. generator constant: 183.01 +- 3.80 Vs/m Raw median generator constant: 186.14 Vs/m Step # 6 elim., 8 remain. Gen.Const.= 183.58 +- 3.65 Vs/m Best 8 Steps: 183.58 +- 3.65 Vs/m ====================================================================== Average of good up-steps is 178.89 Vs/m Average of good down-steps is -186.40 Vs/m When this asymmetry (most likely due to sensor nonlinearity) is removed, the scatter of the generator constant is reduced to +- 0.30 Vs/m writing 4000 samples into file dispcal.stp Plot of step variance is in percent and limited to 1% ======================================================