Although I cannot reveal any detail about the RF circuit at the moment, I still post one picture here for reference. I designed the circuit by the enlightenment of Class D audio amplifier, hence the cicuit is very cool in amplifying the time radio. In our emperical test, the cicuit can generate 50 Vpp voltage swing without any use of heatsink. In the end of this summer, I will make a 500V DC power supply to test its performance. That is our goal, 1000W output.