Two antennae have been installed in JET and operated to the maximum design capability of the generators. 4.5 MW, 10 MJ have been coupled to the plasma which heated up to a maximum stored energy of 3 MJ with central temperatures of Te0=5 keV and Ti0=4 keV without increase of the relative impurity concentration. Degradation of energy confinement is observed according to an L mode scaling. The effect of k/sub //// shaping is discussed using a quadrupole antenna. Hydrogen and helium 3 minority heating regimes give similar results.