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150w RF amp for 88-108MHz (band 2). The amp has 2 stages using a mosfet for the first stage (blf244) which requires 0.5-1watt of RF input to get about 20watts to drive the final stage (the good old SD1407) which can push nearly 200watts on this design! This design is more or less broadband however i added 2 variable capacitors after each stage for optimum matching and power output. Make sure the trimmer and the capacitors after the final stage (SD1407) are a high voltage kind (at least 200v). The power on this amp can be varied by adjusting the bias voltage (using the white pot) to the BLF244 mosfet. I added a zener diode onto the bias supply to protect the (expensive) transistor from too much bias voltage.
150W RF amplifier heatsink
150W RF amplifier circuit schematic and PCB layout