I stumbled into some posts on PSN in the 1996 era regarding atmospheric
pressure changes and their relation, if any to seismic activity.  Has
there been any further research in this area?  (forgive me for being too
lazy to read 7 years worth of posts to see.)  I built an extremely
sensitive barometer using a manometer and optical switch based on a
Scientific American article and later modified it into a "dry" version
using a flexible diaphragm with a magnet on it and a Hall effect sensor.
It measures pressure indirectly by matching atmospheric pressure with a
heated chamber and measures the pressure indirectly as temperature
change of the heated chamber.  The liquid version was sensitive to
within about 3/4 inch of water and the dry one is pretty close to that
value.  It's pretty hard for me to correlate the pressure changes with
any activity here as seismic activity is pretty small on this piece of
the globe.
=20
John Nelson





I =
stumbled into some=20
posts on PSN in the 1996 era regarding atmospheric pressure changes and =
their=20
relation, if any to seismic activity.  Has there been any further =
research=20
in this area?  (forgive me for being too lazy to read 7 years worth =
of=20
posts to see.)  I built an extremely sensitive barometer using a =
manometer=20
and optical switch based on a Scientific American article and later =
modified it=20
into a "dry" version using a flexible diaphragm with a magnet on it and =
a Hall=20
effect sensor.  It measures pressure indirectly by matching =
atmospheric=20
pressure with a heated chamber and measures the pressure indirectly as=20
temperature change of the heated chamber.  The liquid version was =
sensitive=20
to within about 3/4 inch of water and the dry one is pretty close =
to that=20
value.  It's pretty hard for me to correlate the pressure changes =
with any=20
activity here as seismic activity is pretty small on this piece of the=20
globe.
 
John=20
Nelson