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Convertion count to m/sec

Your Question: 
Dear IRIS Pascal Instrument Center, My name is Akhmad Fanani Akbar, I am from Institut Teknologi Bandung. I will do my thesis with focal mechanism topic. And I need some information with Geospace Y-28 (GS11-3D) High Frequency Sensor. Did IRIS Pascal Instrument Center have information about A0 and ratio count --> m/sec about this instrument? Because I couldn't found it in and when I try to contact geospace by email, they never reply my email. I hope you can help me to solve my problem. Thank you, Best regard, Akhmad Fanani Akbar Geophysical Engineering Institut Teknologi Bandung
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Hello Akhmad.  These two pages may help you.

The first is our Sensor Comparison Chart:

Here is the information from that page on the Y-28 Sensor:

  • Sensor : Y-28-3D
  • Manufacturer : Oyo-Geospace
  • Power : passive
  • Corner Frequency : 4.5 Hz
  • Damping : 0.707 critical
  • Sensitivity : 32 v/m/s
  • Poles and Zeroes :  2 poles, 2 zeros

A second page, "Working with Responses to Get Units of Ground Motion", explains how to get the units of ground motion:
                                             Amplitude(counts) * A/D conversion factor(V/counts)
ground velocity (m/s)     =     ------------------------------------------------------------
                                             Gain * Sensitivity (V/m/s)

The Sensitivity for the Y-28 is 32 v/m/s. Note that you will have to include a conversion factor for the specific type of DAS used (RT130 versus Q330, for example), and factor in the Gain, etc.

There is more information on the Y-28 here:

and Poles and Zeroes for this sensor are listed here:

Good luck!

Dave Thomas