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Posted by Walter Hamler on May 20, 2001 21:27:18 UTC

If you have a recent copy of S&T, JMI advertises in every isue. Just ask for the 2" Monorail Kit, currently 79.95. You can specify either a flat base or a radius base. The radius is perfect for a 12" id tube that you would probably use; the flat is for truss tube designs if you go that way.
I plugged your numbers into my version of newt and a 1.97" secondary will give 100% illumination over a a .16 diam, too small for even planets and the moon. A 2.14" diag give a barely adequate .385 coverage for 100%, I prefer at least .4~.5" coverage for the 100% cone. Naturally the 75% cone is bigger than you would ever need, but you have to get those minimums taken care of first.

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