The coupled linearized VLASOV equations for a multicomponent system with charged particles are solved approximately by an iteration procedure. This system may either be a partially or fully ionized gas plasma, or the electron gas of a nondegenerate semiconductor treated in the one-band effective-mass approximation. The system is under the action of a space- and time-dependent external electric field and a homogeneous and constant external magnetic field. Collisions between electrons and ions (or phonons) are taken fully into account by a complete set of BHATNAGAR-GROSS-KROOK collision integrals. The collision terms are expanded in powers of the ratio electron mass/ion mass. In the first order, the electrical conductivity tensor is calculated, and a general dispersion relation is derived. A proof of the H-theorem is given in an appendix.