Sender amplifier with phase shifting network - used for fundamental or harmonic frequency so that fundamental peaks are reduced

摘要

The amplifier has an output stage (4) with an output circuit, containing a resonant circuit tuned to the fundamental frequency to be amplified and, in order to improve the efficiency, at least one resonant circuit tuned to a harmonic. The output stage is controlled by a driver element (1) delivering a driving output voltage with at least one harmonic which increases peak values of the drive output voltage against the fundamental. The phase shifting network (3) for the fundamental and/or the harmonic is inserted between the driver element output and output stage control electrode, so that this harmonic reduces peak values of the fundamental.