Hi all, On John Lahr's web site is acouple pictures of his spectroscopic graphite rod levitating over a unique magnet setup. Especially good is a video of the graphite rod freely oscillating back and forth over the magnets and within its channel. Its a 1.2mb MPEG download, which will play on the Microsoft Windows Media Player, and with that programs controls, it can be replayed of course. Its unknown whether it will play the video with other browsers? See: http://lahr.org/john-jan/physics/maglev/glev/ This particular basic type layout was found by David Lamb around January 2001; and it seems to have a real good potential for use as a tiltmeter/seismometer with development of a light sensor circuit, and the application of a aluminum damping medium with a "flag" to discern motion. Currently the magnets are not available per Forcefield, but its hoped that a quanity become available ~ June/July 2001. The spectroscopic rods used are likely old stock (circa 1960's-1970's), but its highly likely that there are sources of similar diamagnetic (or better or worse) 1/8" spectroscopic rods available. One real advantage with this graphite is that its cost is greatly lower than with some other special graphite used in levitation. There are plus's and minus's possible with this type of layout. Probably most evident is that the levitation assembly is itself most of the usual "boom, mast, mass and etc", involved in construction. When leveled and the rod length adjusted, its possible to get periods of from ~ 1 sec up to ~ 4 seconds. One negative is that with the "mass" being lightweight, it will very likely have a unknown amount of Brownian noise associated with it. Regards, Meredith Lamb __________________________________________________________ Public Seismic Network Mailing List (PSN-L)
Larry Cochrane <cochrane@..............>