Thanks, Joe, it's easy to make one, and I can't take credit for the idea. I think it came from Scientific American though I can't remember with certainty. All you need is a good magnet, a small first-surface mirror, some fishing line, and a small, cheap laser pointer. I use a two-dollar red one from Walmart. You also need to install it in a place with NO air currents at all. Mine was suspended at first in a glass milk bottle. Then I stuck it in the basement where it worked OK until I installed central air in the house this spring. Now I have to have the air conditioner off for an hour or two for it to settle down. I'm going to make a plexiglass isolation chamber for it (read: "box"), so I can use it with the AC running. Also if you can't find monofilament fine enough, use the thinnest, finest cotton or silk thread you can find. On 8/4/10, Joe Bauman <josephmbauman@yahoo.com> wrote:
Chuck, what an amazing instrument! -- Joe