"A Rememberance of Art Leonard" by Tom Fox and "Art Leonard in His Own Words" by Arthur S. Leonard, in The Newsletter of the Sacramento Valley Astronomical Society, vol. 58, No. 11, November 2001 at http://www.skywatchers.org/newsletter/nov-01.pdf The articles begin on page 2.
Bibliography On Stressed Mirrors at http://www.megspace.com/science/sfe/i_en_smt_bibl.html
Jack Borde's 10 inch Yolo at his Vista Diablo Observatory: http://www.atmsite.org/contrib/Borde/borde_yolo/borde_yolo.html Jack was a friend of Art Leonard and built this scope at about the same time Art was building his 12 inch. (The 12 inch has been dismantled for some years after having been installed at two different locations.)
Yolos http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/yolo.htm
Yolo Info at http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/yoloinfo.htm
Erwin Herrig "Figuring a Toroidal Mirror Specifically for a Yolo Reflector" at http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/erwin_c.htm
David Stevick's Home Page at http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/home.htm
Weird Telescopes http://bhs.broo.k12.wv.us/homepage/alumni/dstevick/weird.htm
"A General-Purpose Yolo You Can Build" by Robert Novack, Amateur Telescope Making Journal, Issue 14, pages 22 - 27.
This article is no longer available on-line and, so far as I know, back issues of ATMJ are no longer available. The article may be included in: The Best of Amateur Telescope Making Journal, Volume 2, William J. Cook, ed., Willman-Bell, Richmond, VA
Leonard, A. S., The Yolo Reflector, Advanced Telescope Making Techniques, A. Mackintosh, ed., Vol. 1, Optics, Willman-Bell, Richmond, VA, 1986) p. 228
Sasian, Jose, Designing a Yolo Telescope, Telescope Making, No. 37, 1989, p. 12
Mulherin, J., A Simple Procedure for Producing a Yolo Telescope, Telescope Making, No. 45, 1991, p. 34
Sasian, Jose M., A Practical Yolo Telescope, Sky & Telescope, Vol. 76, No. 2, August 1988, pages 198 - 200
Sinnott, Roger W., Editor's Note, Sky & Telescope, Vol. 76, No. 2, August 1988, pages 200 - 201
In the February 2002 issue of Sky & Telescope, Richard Feinberg, Editor, announced that during 2002, the Sky & Telescope web site, http://skyandtelescope.com, will contain a searchable index to the magazine's entire run, and articles for the last several years.
The Yolo telescopes I have seen pictures of, or read descriptions of, all have fully enclosed tubes. In light of recent work on mirror cooling and reduction of thermal boundary layers in front of mirrors and inside tubes, it seems to me almost imperative that both mirrors of a Yolo telescope should be cooled by fans blowing across their front surfaces. In addition, the tube should have openings for warm air to escape, possibly augmented with exhaust fans.
Richard Buchroeder, in a note in Sky & Telescope, remarked that the images in a Schiefspiegler telescope improved markedly when he cut away much of its tube. This experience indicates that ventilation is a real need in unobstructed telescopes. (I am sorry, I do not have the reference to Richard's note at this time.)
For more on mirror cooling and the effects of thermal currents, see:
Alder, Alan, Thermal Management in Newtonian Reflectors, Sky & Telescope, Vol. 103, No. 1, January 2002, pages 132 - 136
Greer, Bryan, Understanding Thermal Behavior in Newtonian Reflectors, Sky & Telescope, Vol. 100, No. 3, September 2000, Pages 125 - 133
Greer, Bryan, Improving the Thermal Properties of Newtonian Reflectors - Part 1, Sky & Telescope, Vol. 107, No. 5, May 2004, Pages 128 - 132
Greer, Bryan, Improving the Thermal Properties of Newtonian Reflectors - Part 2, Sky & Telescope, Vol. 107, No. 6, June 2004, Pages 122 - 126
Video examples from Bryan Greer's article are available at http://skyandtelescope.com/howto/scopes/article_1182_1.asp
or at
http://www.fpi-protostar.com/bgreer/may2004s%26t.htm This second link has more content than the one at S & T.
More of Brian Greer's telescope research is at http://www.fpi-protostar.com/bgreer/
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