In a message dated 2/15/00 9:08:13 AM Pacific Standard Time, RLLaney@....... 
writes:

>   Baker originally designed the device 
>  as a vertical-motion seismograph.
>  
>  My friend has two questions:
>  
>  1)  Could this article be like the one describing the ADXL05 sensors in SA 
a 
> 
>  couple years ago where the readers were mislead into believing that the 
>  sensors would work for detecting distant earthquakes, that is, another 
> device 
>  that doesn't quite measure up as advertised?
>  
>  2)  More important, could this device be modified back for use as a 
>  reasonable vertical-motion seismograph?
>  
>  Would appreciate hearing from anyone who has seen the article and/or is 
>  familiar with this device.
>  
Hello 

I have made a gravitymeter from a vertical seismometer.  Basically, I use dc 
voltage to lift (or lower) the coil to the stop or the maximum travel 
position.  Then the DC voltage is removeed and the voltage generated by the 
coil coming to rest is measured.  The farther the coil travels to come to the 
resting position the higher the voltage. Other geophones are in the circuit 
to reduce normal seismic noise.   I am still testing this circuit for 
sensitivity.

George Erich
Seismic Exploration Consultant
P. O. Box 2011, Norwalk, CA 90651, U. S. A
Phone (562) 868-6013
e-mail GeE777@.......
33 53.90N
118 04.53W
http://hometown.aol.com/gee777/myhomepage/profile.html

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