 In 1983, the portable telescope was moved back to Green Bank for another function to become a tracking station for Space VLBI satellites.The new portable telescope was put in place for interferometer operation until 1988 when the GBI reconfigured to 2-element interferometer with 85-3 taken out to become geodetic VLBI and pulsar monitoring telescope.The GBI resumed operation as a radio monitoring instrument on Nov. 22, 1996, operated by NRAO and supported by the NASA High Energy Astrophysics program.