In 1972 the building was enlarged to accommodate new beamlines, and by 1973 there were ten ports, and beam currents were up to about 50 mA. A new injector, a 40 MeV microtron, was installed as an injector in 1974, replacing the original MURA accelerator that had been used until that point, and within a year currents exceeded 150 mA, with typically over 30 hours of beam per week. A stored beam of 260 mA was achieved in 1977. In October 1974 the National Science Foundation took over funding from the Air Force.