Utilizing a ring shaped transducer with a 7 inch clear-through center hole this new Microgon shaft encoding system has achieved a standard deviation accuracy of 0.26 seconds of arc when operated at a resolution of 221 or 2,097,152 counts per turn. The ring-type transducer is suitable for radar on-axis installations with waveguides passing through the center. Other applications include rate tables and tracking instrument mounts. This Micro gon system comprised of a transducer, transducer controls, dual preamplifiers, and one box of transistorized electronics has been developed for natural binary or 8, 4, 2, 1 coded decimal outputs of digit and complement with visual displays. Two of these systems are in use on ADVENT radar antennas.