Ramped accelerating gradients in drift-tube linacs are made possible by post couplers with extreme differential coupling between adjacent accelerating gaps. By bringing the energy of the beam up through ramping, better overall control of longitudinal emittance can be accomplished and a more compact accelerator achieved. Such a machine has been designed at Los Alamos and built through industrial participation with the Hanford Engineering Development Laboratory (HEDL), the Brobeck Corp., and Grumman Aerospace Corp. The design of the Ramped-Gradient Drift-Tube Linac (RGDTL) involved development of high-powered drive loops, specially instrumented drift tubes, and a new rotary-type dynamic tuner. The assembly of the machine from the industrial components has been completed, and it is now installed and in operation at the Accelerator Test Stand (ATS) in Los Alamos. 6 refs., 7 figs.