“…The solid-state devices present a smaller size, longer lifetime, more reliability, and cheaper price than the vacuum-tube equivalents. Moreover, if transistors are tuned to operate in a switching mode, the RF source may generate high power with a high efficiency, up to 100% in principle [2,3]. For example, a 2.7-kW power amplifier operating in a class-E/F mode was implemented at 29 MHz by combining eight vertically double diffused MOS transistors [4].…”