Ian,

Now that you have mentioned that your tiltmeter is probably an electrolytic
bubble, I meant to mention that most of these have complex electrode/
electrolyte chemistry and must be operated as an AC bridge. If you are
inclined to probe circuits with a multimeter, do NOT try to measure
the electrode resistance with a DC ohm-meter. The slightest DC current
will ruin the sensor by plating the coating off the electrodes. This is
of particular concern for anyone who finds the biaxial Rockwell sensor 
in an electronics surplus store, since the electrodes are plated onto the
curved glass surface, and will disappear almost instantly if a meter is 
applied. In fact, it may already be ruined inside the SS shell.  I can 
supply the schematic to properly operate this bubble.

Sean-Thomas


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