  Muon acceleration from 30 to 750 GeV in 72 orbits using two rings in the
1000m radius Tevatron tunnel is explored. The first ring ramps at 400 Hz and
accelerates muons from 30 to 400 GeV in 28 orbits using 14 GV of 1.3 GHz
superconducting RF. The ring duplicates the Fermilab 400 GeV main ring FODO
lattice, which had a 61m cell length. Muon survival is 80%. The second ring
accelerates muons from 400 to 750 GeV in 44 orbits using 8 GV of 1.3 GHz
superconducting RF. The 30 T/m main ring quadrupoles are lengthened 87% to
3.3m. The four main ring dipoles in each half cell are replaced by three
dipoles which ramp at 550 Hz from -1.8T to +1.8T interleaved with two 8T fixed
superconducting dipoles. The ramping and superconducting dipoles oppose each
other at 400 GeV and act in unison at 750 GeV. Muon survival is 92%. Two mm
copper wire, 0.28mm grain oriented silicon steel laminations, and a low duty
cycle mitigate eddy current losses. Low emittance muon bunches allow small
aperatures and permit magnets to ramp with a few thousand volts. Little civil
construction is required. The tunnel exists.
