The invention concerns an apparatus for generating and/or detecting radio frequency (RF)-B1 fields in an investigational volume (10) of a magnetic resonance (MR) device, wherein the apparatus comprises a tubular surface coil (1; 20; 30; 41-44; 51-54; 61) which is formed from a conducting strip and is capacitively closed at least two neighboring ends, wherein the ratio between length L and width W of the strip is 30, and wherein the volume under investigation (10) is disposed outside of the space surrounded by the strip, bordering an outer surface (9) of the surface coil (1; 20; 30; 41-44; 51-54; 61) such that the B1 field lines, generated by the surface coil (1; 20; 30; 41-44; 51-54; 61) in the volume under investigation (10) extend substantially parallel to this outer surface (9) thereby producing an NMR transmitting and receiving apparatus with improved properties, in particular, one permitting precise influence of the distribution of the RF-B1 field.