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Hello everyone!<br>
Ok, where to begin?<br>
<br>
I have to calculate the PGA (peak ground acceleration) of some events, and to do that I have 2 options:<br>
<br>
1) Use the SAC function TRANSFER to convert the original displacement data to acceleration.<br>
2) Manually convert the data to velocity (using seismometer and digitizer parameters), and then differenciate to acc.<br>
<br>
Why is this 2nd option there?<br>
Because I've tried to understant how to build the POLEZERO file too many times. The poles and zeros aren't a problem (I've found them in the seismometer manual), but to find the constant value, I've seen a lot of formulas. One of them is:<br>
CONSTANT = A0 * SensorGain * DigitizerGain<br>
<br>
where A0 is the "normalization factor". I can't find it in the seismometer manual. Theese are the informations I have about seismometer and digitizer:<br>
<br>
- Seismometer: KS2000 Geotech Instruments<br>
- Seismometer seismic output: 40V pp<br>
- Seismometer sensibility: 2000 v/m/s<br>
<br>
- Digitizer: SMART24 Geotech Instruments<br>
- Digitizer LSB value for 40V pp: 3.271096e-6 V/count<br>
- Digitizer Gain: x 64 (multiplication)<br>
<br>
As far as I know, displacement data is given in counts<br>
<br>
Any ideas with the constant calculation? or should I try to calculate acc manually with the conversion to velocity (using parameters) and the differentiating?<br>
<br>
Thank you very much.<br>
<br>
---------------------------------------------------------- <br>
Danilo de Oliveira Domingos <br>
University of São Paulo<br>
Brazil<br>
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