Omni-Bearing Selector 336A-2 for Collins Radio VOR-102 Nav System DC-7
Here is an Omni-Bearing Selector 336A-2 as used in the 1950's era Collins Radio Navigation System VOR-102. The selector enables selection of the desired track and provides to-from information. The right hand knob selects the course, and the left hand switch reverses course 180 degrees. See photo of the instrument in the 1959 Collins Radio catalog page, and the front page of the Collins sales brochure. Measures 3.25in diameter and ~6in deep. The VOR-102 was used in a variety of aircraft during this era, including the Douglas DC-7, see photo of cockpit with one of these selectors appearing in front of the pilot and one in front of the co-pilot.