On Tue, Oct 20, 2009 at 8:12 AM, Randall Peterswrote: (Clip) Randall, ** In regard to the Kinemetrics SH-1; I'am having difficulty visualizing the spring directlyabove the horizontal pendulum mass. Might you and anyone have a PDF file with a picture/s they could share? > A commercial horizontal seismometer that successfully uses > the same physical principle is the Kinemetrics SH-1. The torque acting in > opposition to gravity is provided by means of a vertical elastic metal strip > (spring) that holds the seismic mass in an equilibrium position directly > above it. The instrument employs two magnet/coil subsystems: (i) one for > Faraday law detection with which every amateur seismologist is familiar, and > the (ii) other one for calibration (by introducing a current to the coil) > and for damping when operational (by placing a resistor across the coil). > > ** Feel free to offer your thoughts on the sensors. > I hae not here mentioned sensor type. For those with interest I can offer > thoughts based on my long-time experience with both velocity and position > types. > > Randall Peters > Meredith Lamb > >
On Tue, Oct 20, 2009 at 8:12 AM, Randall Peters = <PETERS_RD@mer= cer.edu> wrote:=A0(Clip)=A0Randall,=A0** In regard to the Kinemetrics SH-1; I'am h= aving difficulty visualizing the spring directlyabove thehorizontal pendulum mass.=A0 Might you and anyon= e have a PDF file with a picture/s they could share?=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0=A0 A commercial horizo= ntal seismometer that successfully uses the same physical principle is the = Kinemetrics SH-1.=A0 The torque acting in opposition to gravity is provided= by means of a vertical elastic metal strip (spring) that holds the seismic= mass in an equilibrium position directly above it.=A0 The instrument emplo= ys two magnet/coil subsystems: (i) one for Faraday law detection with which= every amateur seismologist is familiar, and the (ii) other one for calibra= tion (by introducing a current to the coil) and for damping when operationa= l (by placing a resistor across the coil).
** Feel free to offe= r your thoughts on the sensors.
I hae not here me= ntioned sensor type.=A0 For those with interest I can offer thoughts based = on my long-time experience with both velocity and position types.=A0
Randall Peters=A0=A0=
=A0Meredith Lamb=A0