Switching-type wide band power amplifier

3-30MHz output 6W(with 13.8V supply)

Circuit

About

This is a non-linear power amplifier with high efficeincy. You can use it power amplifier for CW transmitter. I emmployed a MMIC MMG3H21NT1(NXP) as a driver and a FET RQA0009 (you can get it in Aliexpress) as a final amplifier.
Because it operate in swiching-way with square wave, it has below advantages,

• Simple (no bias circuit)
• Frequency dependence of output power is flat (see below picture: with 1mW input)
• High efficeincy (η > 60% with 13.6V)