In my research for more background information about the Gajdusek-Kozelsky telescopes from the Zdanice Observatory I found an article in the Slovak astronomy magazine about a similar 20cm refractor build by Kozelsky.
After more than two years of hard work, the famous telescope builder František Kozelský from Old Běleja (Ostrava) build a refractor for observatories in his workshop. The telescope will be installed in the observatoriy of Kysucké Nové Mesto.
It is the largest device of this type made by František Kozelský and one of the largest refractors in the Slovak Republic, dedicated to amateur astronomy. We asked the telescope designer a more detailed description of the new apparatus. He is willing and show the huge telescope. The telescope was completely setup in the hall of his house. It’s the only place where he can mount the telescope.
In the next editions of our magazine we will report on the further installation of the telescope in the observatory
The device is built on a strong conical steel frame which ensures the stability of the telescope. The lens is from Zeiss Jena (type AS, 200 mm, f = 3000 mm). Equatorial mounting is driven by a synchronous electric motor (10 W, 3000 rpm] via a gear box with a planetary gear, which allows using the second electric motor, A hand box allows guiding in the right accession. The drive is mounted in such a way that there is no vibration. The gearbox is permanently filled with oil. The telescope is equipped with hour circles for fine adjustments . On the setting circles eyepieces are installed for a detailed read out.
The focuser is designed for rapid exchange of eyepieces and other auxiliary equipment. On the telescope tube a Schmidt Camera is mounted with a mirror diameter of 200 mm f: 2.44. The camera has a field of view of 7 degrees. The diameter of the film cartridge is 58 mm. The Schmidt camera was made by Ing. Wilhelm Gajdušek.
The telescope is equipped with a viewfinder with a diameter of 80 mm ff = 450 mm], which magnifies 16x. the viewfinder includes eyepieces for 75, 110, 150, 200, 313 and 600x.
Other accessories are: a zenith prism, also a Herschel wedge for direct observation of the Sun with polarizing filters and various other filters, a 3 eyepiece revolver for quick exchange of eyepieces and a solar projection screen 35 x 35 cm.
František Kozelský spend 2.5 years building this telescope
Kozmos, March 1980
The 20cm telescope described in this article is still in use in the Hlovohek Observatory.