An Austin ring transformer is a special type of isolation transformer used for providing power to the aircraft warning lights and other devices on a mast radiator antenna insulated from ground. In the Austin transformer the primary and secondary windings are separated by an air gap, so that the high voltage on the mast cannot get into the low voltage lighting supply wiring, causing safety hazards. It is named after its inventor, Arthur O. Austin, who graduated from Stanford University in 1903 and who obtained 225 patents in his career.