How is this done. Been reading about sputtering and DC sputtering is extremely simple. However, i'm not very experienced with RF circuitry so understanding exactly how to design that circuit confuses me a bit. Been reading about RF circuits but to generate an RF signal every method I find uses DAC converters and is more suited for music then high voltage applications like this. I understand how the impedance matching unit works fairly well and they use variable vacuum capacitors to manage the high voltage. Given that the impedance matching unit is done with a simple L matching ciruit using analog components I imagine the power supply has to do with analog components also. My google fu isn't finding much. I know radio predates the digital transistor so exactly how using analog components do you create a radio signal and tune the frequency?