[en] The heating results in the LH frequency range (f = 2.45 GHz, Psub(RF) <= 250 kW, Psub(S) <= 6 kW/cm²) both in the electron and ion regimes are described. Efficient electron heating was observed for n-bar <= 5.10¹³ cm^-3. Increases of the peak electron temperature up to 700 eV were measured. At higher densities the interaction with electrons disappears. In the ion regime fast neutral tails and neutron enhancement were observed. The influence of plasma boundary conditions on the penetration of the wave is demonstrated. The principal physical problems are pointed out and some possible conclusions are given. (author)