An amplifier includes a Field Effect Transistor (FET) or a Bipolar Junction Transistor (BJT) with “hard saturation.”; where the FET or the BJT to has a nearly constant drain or collector current when the drain or collector voltage is greater than the pinchoff voltage. The amplifier further includes a bias network, configured to provide a DC voltage to the FET or the BJT, a means for isolating the DC voltage from the matching network, an electrical load, and a matching network which transforms the electrical load to a resistance between the drain and the source or the collector and emitter which causes the drain or collector voltage to be greater than the pinchoff voltage over the entire cycle of the sinusoidal voltage applied to the gate, whereby the amplifier is linear.