Broadband Class-E Power Amplifier for HF and VHF

The power amplifier described here uses a 50-V gemini MOSFET and operates in class E to produce up to 200 W from 1.8 to 128 MHz. The circuit incorporates a broadband input so that frequency changes require only retuning or switching of the output filter. The efficiency varies from 90 percent at 1.8 MHz to 70 percent at 128 MHz. The amplitude-modulation linearity is excellent, making it well suited for use in a Kahn-technique (EER) transmitter