Note:

The two large blocks at the bottom show the final output, including the damping factors, the damping resisters and the transduction gains for the three different damping factors.

Addition Information:

        R1 is a 100K 1% resistor in series with the signal generator, while R2 represents the thevenin equivalent generator
        source resistance after switching in a 20K 1% resistor in parallel with the geophone.  Hence each geophone is tested
        with 100K and 16.667K damping resistors to determine the various parameters. The resonant frequencies were only
        measured with the 100K damping resistor. Both positive and negative step responses were measured and an average
        computed for the final results. Every cell with a pale yellow-green background shows the data entered and all of the
        remaining plain background cells show the calculated results.  Also note that the moving mass is in units of grams.

Summary:

        Based on the very small sample size for the horizontal geophones (2), I'm seeing a -4% to +3% variation in the resonant
        frequency and about a +/-0% variation in the open circuit damping factor, all of which are well within the +/-10% specs.
        The vertical geophone has a -19% resonant frequency deviation (obviously a much lower frequency than the spec range)
        and a -4% damping factor deviation, both are relative to the manufacturers nominal values. All three geophones are well
        within their +/-5% coil resistance specifications.

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