Here is a photo of the seismometer
designed by Pete Rowe. The flexure
hinge is in the forground, the flat
paddle is a pendulum platform
made of circuit board material
which holds the coil and a small
fishing weight. The magnet is a
large magnetron magnet, with a
pole piece to concentrate the
magnetic field.

This is a very successful design in
that it has recorded nice seismo-
grams from as far away as Iran
from it's location in San Jose,
California.