Abstract: A sun tracker including a dual axis support for following diurnal movement of the sun and a drive mechanism for providing motive force about a first axis of the support. Accurate movement of the tracker about a second support axis is caused by a system of cables and a cooperating cable engaging arcuate surface shaped to produce the necessary movement about the second axis to maintain the tracker in appropriate orientation with the sun throughout the day. Seasonal adjustment is effected by adjusting the cable lengths.