A system of electromagnetic coils for examining bodies of large size such as the human body by means of nuclear magnetic resonance (NMR), comprising a first set of coils designated as an electromagnet for producing a uniform magnetic field H.sub.0 in which the body to be observed is placed, and a second set of coils designated as NMR coils for producing a high-frequency (HF) magnetic field (H.sub.1) at right angles to the field H.sub.0 of the electromagnet, wherein:
- the first set of coils comprises at least two symmetrical coils spaced at a sufficient distance from each other to permit introduction of the body to be observed between said two coils in the transverse position at right angles to the field H.sub.0 of the electromagnet;
- the second set of coils comprises at least one solenoid coil placed around the portion of the body to be examined.