What was the name of the radio telescope the surpassed the Dwingeloo Radio Observatory?
Dwingeloo Radio Observatory:  At the time of completion it was the largest radio telescope in the world, but it was overtaken in 1957 by the 76-m Lovell Telescope. Lovell Telescope:  When construction was finished in 1957, the telescope was the largest steerable dish radio telescope in the world at 76.2 m (250 ft) in diameter;
Lovell Telescope