300 W PA Using 3 x RD100HHF1 by Sergey EX8MLE

This PA has been designed by Sergey EX8MLE and uses three Mitsubishi RD100HHF1 FETs.

Please contact Sergey EX8MLE if you would like to buy an assembled PA or a PCB.

Sergey has also made a video of his latest PA.


Frequency Range  –  70-72 MHz

Input/Output impedance – 50 Ω
Vdd = 15,6 V
Idq = 1,00 A per transistor
Pin = 5 W single tone
Pout = 300 Watt  CW
Id = 33 A
Gps = 17,8 dB
nD = 58%

Class – AB

Circuit diagram

Low pass filter



PCB with components

Combiner/splitter with low pass filter