I decided to add one more stage behind the amplifier. This will add another abt. 10dB of gain. Mitsubishi MOSFET RD06HHF1 in class A was used as a final stage in every section. On the right hand side of the board 2 dB attenuators and combiner are visible. Total gain of every amplifier including attenuator is abt. +28 dBm. It means that at the output of the combiner I can calculate with max. +22 dBm of output signal level, depending on the frequency (+21 dBm when LPF will be added). Amplifiers use an analog gain control, stages in every section will be shielded separately.