[en] A system consisting of 10 wire spark chambers with ferrite core readout is described. This system was used in an investigation of the diffractive dissociation of π^- and K^- mesons on complex nuclei. The wire spark chambers were used together with the JINR magnetic spark spectrometer to determine the momentum and direction of flight of incident particle beam on the target of the spectrometer. Beam parameter measurements were carried out: momentum distribution σ(Δp/p) =+- 0.4%, beam dimensions: σsub(vert)=2.9 mm, σsub(hor)3.9 mm, angular distribution - σsub(vert)=0.44 mrad, σsub(hor)=0.32 mrad. The accuracy of momentum determination was 0.15%, and that of coordinate measurement was 0.3 mm