Updated: 4.25.10


4" Unitron Model 160 Telescope

I remember drooling many a night over a Unitron calalog, glancing at the many models and tons of accessories offered. I coveted even the small 60mm, but ended up with a Montgomery Wards 60mm alt-az, as the Unitrons were well out of my price range.

Some 40 years later, these refractors are in as much demand and highly sought after as a collector's item. I was very fortunate to recently come into possession of a 4" Unitron refractor. Not only was it a 4", but it was the model 160, the Photo-Equatorial! It sat in my closet for almost 3 years after I picked it up, so I finally decided to take it out and inventory the scope. It was missing 6 items, with the threaded counter-balance shaft and the counter-balance weights being show stoppers. Also missing were the clock drive weights (since made), shelf illuminator, short manual RA control (since picked up) and the 5/16" bolts to mount the accessory tray to the tripod (replaced with Home Depot bolts, but will get a good set of SS bolts for it eventually). There is a manual flex cable for the RA axis, but I didn't install that for the pics. A good friend machined a stainless shaft for me (free!), so I requested the diameter of that shaft to be 1.244". Why 1.244"? That allowed me to use my 7 lb Losmandy weight to setup the scope (as seen in the pics). Well, I have since purchased a new shaft (the last one available from Unitron) and had all of the weights, both shaft and clock drive, made up by a good friend. I used Krylon black krinkle paint to finish them up.

Here are some views of the scope setup in my living room and an image of the weights that were machined and painted. Fully assembled, it is a monster, even in this room with 12 foot ceilings. To give a point of reference, the Losmandy counter-balance weight is about 1" below eye level (well, for a short guy like mel!). Click on any thumbnails to see the set of larger images.

As you can see, the scope is driven by the mechanical brass clock, a true work of art. The machining is impressive, as is the clear plexiglas sides to show off the mechanism. Not shown are the 13 eyepieces (OR4, OR5, OR6, H6, SYM7, SYM9, SYM9 x-hair, K12.5, K18, R25, 40 mono, K60 and one unmarked - possibly for the camera tube?). There's also a pristine Super UNIHEX, Herschel wedge (has a small corner chip), erecting prism, super rack and pinion focuser, Uniclamp camera adapter, and Astro-camera. The right angle prism tube was damaged, but a replacement has already been secured. At the same time, a Polarex Duetron was picked up for it, as well as the solar and moon filters (button types). There are some small scratches on the tube and the dew shield has a couple of small dents, but overall, a very impressive, imposing and beautiful setup. Here's a last view from the front and weights for the scope and clock drive.

The next step is to actually take it outside and view something! 8-)

The moon, star clusters and planets should make nice test targets for the optics. I also have a modified dovetail to mount the 4" cradle on my Titan, so I can check it out more easily. No excuses now. Pictures of the accessories are forth coming. Stay tuned...