In this work, a rectangular coaxial transmission line based power amplifier is discussed. This transmission line is created by sequential photolithography and plating processes, resulting in a very wide band, dispersion-less transmission medium which includes integrated passive components. This approach yields a number of advantages over conventional microstrip circuits. This 3D micro-machining technology, called Polystrata TM technology, in which the circuit is the package, and the package is the circuit, enables one other important and far reaching advantage.