This PA has been design with pre matched power FET that could be found on fleamarket.
The first stage is based on FLC253MH driver followed by two FLM7177-4 power FET.
The power of the first stage is divided on the two branche and then added up on the output. Each stage has around 7..8dB gain. All layout or transitor disymetrie produce power on the rejected port of the coupler (on input and on output) which are terminated on external 50 ohms load.
The power supply is based on 7660 negative DC converter which produce Gate voltgage for the 3 power FETs. The Drain is powered trought LT1084 serial regulator. A security signal avoid Drain voltage in case of Gate voltage failure.
Each Drain current could be ajusted with separated pot. All PSU is included on the RF PCB.
This PCB design could be used with higher power transistor (2x10W or 2x30W) but power supply has to be modifed accordingly

RF Adjustement:
1° Adjust 2nd stage without first stage mounted. Inject small power and add stub to get max power on output and min power on reflected output. 7..8dB gain should be measured with standard device.
2° Mount driver FET and add stub to maximise outup power.
3° Increase input power to found 1dB compression point.
4° Optimise stub position at full power

The size is 100y160mm and is monted on heavy duty aluminium drilled box to avoid excessive temperature. Silver glue could be used to provide perfect RF electrical contact (Critical on the SMA port area)
Measurements:
P-1dB = 8.7W (39.4dBm) at gain=14.6dB
Rlin~-20dB Bandwidth~240MHz (4%)
Power consumption = 2.3A on 13.8V

The PCB file on electronic format could be ask on my e-mail adress.