Abstract: A system providing linear amplification of a signal including a pulse duration modulation of the signal upon a carrier signal, the system further including a plurality of amplifying units which are sequentially activated by the modulated carrier. The amplifying units are arranged in the form of a bridge circuit, the nodes of which are coupled to a load, the amplifying units including transistors which are driven alternately in states of conduction and nonconduction for maximizing power coupled to the load while minimizing power dissipated in the transistors. A filter connected between the amplifying units and the load attenuates signals at the frequency of the carrier so that the waveform of the signal applied to the load duplicates the waveform of the signal at the input of the system.