Abstract: The present invention relates to a matching and tuning network for connecting a source of RF power to a complex load. The network is comprised of a primary circuit and a secondary circuit. The primary circuit is comprised of a fixed capacitor connected in series with a primary winding of a coupling transformer connected to said source of RF power. The secondary circuit is comprised of a series connection of a secondary winding of said coupling transformer and a variable capacitor connected to said load. The network is further comprised of an input voltage sensor; and an input current sensor both connect to an impedance detector and a phase detector. The impedance detector controls an encoder for varying the coupling between the primary winding and the secondary winding of the coupling transformer to maintain a constant input impedance. The phase detector controls the same encoder for varying the capacity of the variable capacitor so as to maintain a zero phase shift at the input to the network.