A novel variant on nuclear magnetic resonance stray field impossible, in principle, to move the sensitive slice by increasaging (STRAFI) is presented in which an additional magnetic ing or decreasing the central field of the magnet, most superfield sweep coil is used to sweep the region of resonant frequency conducting NMR magnets operate in the persistent mode through a stationary sample. Variants on this technique using an and great care is taken to ensure the stability of the central integral superconducting field sweep coil as part of a spectroscopy field. Thus it is generally not practical to change the field magnet and a room temperature field sweep coil mounted inside over the course of an experiment. The first technique relies an imaging magnet are detailed. One-dimensional profiles of ''Perupon varying the magnetic field generated at the center of spex'' and polytetrafluoroethylene samples are presented. The rethe magnet by the addition of a superconducting field sweep sults from both superconducting and room temperature field sweep coil within the windings of the magnet. At the University coils compare favorably with ''conventional'' STRAFI. แญง 1998 of Kent we are in possession of a vertical bore magnet with Academic Press