Geoff,
Look at the simulator provided my Bob McClure at this =
site.
http://site=
s.google.com/site/bobmcclure90/springcalc
It will help you design a longer period but you will see that =
after 3
seconds just a very small change becomes unstable. I have not =
measured
G. The coil is not very good and I did not intend it as =
permanent.
Even so it is working well for the near term. I need a larger =
diameter
center pole extension and then to make a coil of finer wire that fits =
the pole.
Randall L. Pratt
Youth for Understanding Area =
Representative
rpratt@.............