RF power amplifiers of high efficiency and low consume are very important for applications where the size of the device is important, such as mobile phones, network sensors or PDAs. The classical operation modes as Class-A, Class-B and Class-AB amplifiers have a good linearity but a low efficiency, in contrast, Class-E and Class-F amplifiers are not linear, but they present a higher efficiency. In this paper, we present a methodology for designing and building no-lineal microwave and RF power amplifiers. To build the amplifiers we propose the use of transmission-lines, that facilitate the practical implementation because of the low availability of a wide range of lumped elements in the market but they can be replaced by transmission-lines.