 The 'Energy Doubler', as it was known then, produced its first accelerated beam—512 GeV—on July 3, 1983.Its initial energy of 800 GeV was achieved on February 16, 1984.On October 21, 1986, acceleration at the Tevatron was pushed to 900 GeV, providing a first proton–antiproton collision at 1.8 TeV on November 30, 1986.