1968 — The Mark I confirms the existence of pulsars.
1968 — The Mark I took part in the first transatlantic VLBI experiment in 1968, with other telescopes being those at Algonquin and Penticton in Canada.
1969 — The Mark I is used for the first time in a VLBI observation, with the Arecibo radio telescope in 1969.
1970s
1970–1971 — The Mark I is repaired and upgraded; it is renamed to the Mark IA.
1972–1973 — The Mark I carries out a survey of radio sources; amongst these sources was the first gravitational lens, which was confirmed optically in 1979.
1976, January — storms bring winds of around 90 mph which almost destroy the telescope. Bracing girders are added.
1980s
1980 — The Mark IA is used as part of the new MERLIN array.
1982 — The 42 ft telescope is built, to replace the 50 ft.