Signal Maintainer Helper under supervision, maintain, install, inspect, test, alter and repair MTA New York City Transit’s railroad signal systems on the road and in the shop. They maintain, service and repair various types of railroad signal equipment, including all-electric, electro-pneumatic, optical, all-relay and mechanical interlocking machines; centralized traffic control machines; electronic code systems; train identity systems; microprocessors; switch machines; automatic train stops; color light and semaphore signals; electronic train control and monitor systems; and related power and control equipment. They keep records, drive a motor vehicle, and perform related work.