L’il Chimp
MY EASILY PORTABLE 150 MM F4.4 SCOPE
Having built two equatorially mounted telescopes,
A 110 mm
which was not so easily transportable ,basically due to the head and
counterweight,
and a 203 mm( 8 inch) 
on a
driven GEM, which is impossible to transport
I decided to build myself a telescope which I could easily lift ( I am 72) and could be carried in a package, fully assembled ( no trusses to remove and attach ) and fully mounted
Obviously it had to be a DOB
To keep the size small I decided to go for a short f no. and a reasonable aperture.
So I decided on a 150 mm dia. f 5 telescope.
After lot of trials, tribulations & failed ideas, here is the final product
It weighs only 6 Kgs(13 Lbs) Rocker Box and Ground Board included and stands only 75 Cms
( 29 in) tall fully assembled
Some details
Spider
, Diagonal mount & Focusser
The spider is made from used Hacksaw blades( with the teeth ground out). Moving the ends up down or in out or forward back allows adjustment of the diagonal in all directions
NEWT showed that I needed a 2 inch Focusser. So I used a PVC Plumbing fixture with 2 mm pitch screw and a travel of 25 mm
The Mirror
The mirror was procured from an Indian Manufacturer of optical goods. The mirror turned out to be 150 mm f 4.4( FL 690 mm) against the f 5( 750 mm) promised. The figure was also not what such a fast mirror should have. Ronchi test on the mirror showed that it is oblate with a prominent central hill. It is 19 mm th. Plate glass and is mounted on three points.
Inside ROC 
Outside
ROC 
In spite of the bad figure, the mirror, surprisingly ,performed quite well. At first light under fairly dark sky, I could see M13,M4,M6, M8 etc quite easily and defined quite sharp. Star images had a slight tail, perhaps due to collimation not being quite perfect. Star test did not yield any significant result as the max magnification available was only 50. I intend to repeat with a Barlow in the next session.