PSN-L Email List Message

Subject: Re: Large earthquake near cost of Canada
From: John Lahr johnjan@........
Date: Sun, 06 Jan 2008 21:10:49 -0800

This image:
shows the construction of the AS-1.  As long as the center of mass of 
the boom is at the same vertical elevation as the boom knife edge 
there will be no horizontal cross-axis sensitivity.  The boom is 
prevented from rocking back and forth by the width of the knife 
edge.  Also, rocking motion would not generate nearly as large a 
voltage, as it would not have the optimum orientation of 90 degrees 
for the cross product of the velocity vector with magnetic field vector.

A knife edge is NOT the best type of hinge.  You can find a lot of 
discussion of better hinge designs in the PSN E-mail archives.


At 07:45 PM 1/6/2008, Thomas Dick wrote:
..... does the AS-1 show any directional sensitivity....maybe as the 
result of improper setup? 


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