A switchable power combiner is disclosed. The switchable power combiner has an output section that is a signal source connected to a transformer section. The transformer section has one or more primaries and a common secondary. The transformer primaries and secondary are acoustically coupled. The primaries or/and the secondary are made of switchable piezoelectric material, such that the acoustic coupling between any primary and the secondary can be switched on or off by electrical control, thereby implementing a switchable power combiner. The transformer secondary is connected to an antenna port. The power amplifier output section is segmented and connected to the transformer primaries. The power amplifier output section has a plurality of power amplifiers and a plurality of reactance elements, either fixed or variable. The switchable power combiner generates different linear load lines by switching on and off the coupling between any primary and the secondary.