A generator of time-variable magnetic fields of a magnetic resonance device having an examination space for registering at least one area to be examined of an item being examined has the following features: the conductors of a gradient coil arrangement of the generator define an area at least partially surrounding the examination space, said area contains at least a partial area which is free from conductors of the gradient coil arrangement and which contains conductors of a radio frequency antenna of the generator, and a field flowback space, inter alia for fields of the radio frequency antenna, extends proceeding from the partial area away from the examination space and is delimited beyond said partial area by a radio frequency shield.