The disclosure relates to an electronic circuit for attenuating harmonics in a power amplifier. The circuit comprises: a printed circuit board (PCB); a first electrical track in the PCB providing a connection from a high band power input terminal of the amplifier to a battery terminal; a first capacitor connected to the first track, the high band power input terminal and a ground reference in the PCB; a first high filter choke connected to the first track and to the terminal; a second electrical track connected to a low band power input terminal of the amplifier; a circuit implemented on the PCB and connected to an output terminal of the amplifier for an output signal from the amplifier, comprising a first filter and a low pass filter, the first filter connected to a 0 ohm resistor which is connected to the low pass filter.