Improvement of the Visual Tracking Theodolite for Satellites

By installing the inductosynchronizer and the digitizer to the azimuth elevation axes, we have improved the visual tracking theodolite for satellites in Yunnan Observatory.With the new encoders, the precision of angle —measuring of the remade telescope has been improved to one arc—second from 30 arc—seconds, and the precision of graduator on the field of view has been improved to 15 arc—seconds from 2 arc—munits.The precision of the static orientation is better than 20 arc-seconds, improved by an order of magnitude.