Re: WTB

Bob Madden (madden@netcom.com)
Thu, 20 Jul 1995 21:15:53 -0700 (PDT)

Ed, last year for the Perseid shower I saw a Dutch design do what you have in mind with the 20-inch Al disk. what this fellow did was use a bicycle light power generator as a motor to drive his shutter. It seems to work for those guys. He did have to start it by hand, but once turning kept going. I suppose a test of the rpm is needed. The photographs I saw were pretty good and it seems the velocity was easily determined. This fellow used 4 to 6 cameras pointed at the correct angle to cover the complete sky and only one shutter. This Idea isn't elegant but might work for you.

Bob Madden

):-{])) <---- madden@netcom.com madden@svpal.org Remember amateur astronomers: "keep looking for the next Universe"

On Thu, 20 Jul 1995, Ed Majden wrote:

> I am looking for a set of 12 1/2 inch or 16 inch Cassegrain/Newtonian
> Optics. Must be of high optical quality. I am also looking for a 300 rpm or
> 600 rpm synchronous, (constant speed), motor capable of driving a 20 inch
> diameter aluminum disk. Intended use is to build an interupting shutter for
> meteor train and velocity studies. If you know where I can get any of the
> above drop me a note at: epmajden@mars.ark.com
>
>