By N.S. Harisankar VU3NSH.
This HF Push Pull Broad Band RF Amp will give 50W output and it is useful to RM96 output stage. All components are soldered on the copper foil side (Track side). For fixing the FETs, use Mica insulation and Nylon bush. Connect the drain connection via eylets at the Top (FET’s Drain pin is not directly used in this PCB). Keep P1 & P2 at -ve (zero) position. Connect a 250 ma meter at the supply line (LK .- Link). Set the P1 for 20ma and P2 for 20ma. The total drain current of 40ma.
If you are using this circuit as a separate unit then connect Carrier Operated Relay (COR) and connect VT +ve supply to VCC line with proper dropping circuit to 7805 input. After setting the drain current 40 ma, then connect 0 to 5 Ammeter or VU meter with proper shunt for TX power indication at link line. PCB is available with the author (VU3NSH). All components in this PCB are on the Track side, so use adequate insulation on component / fix all components 2 to 3 mm above the Track side to avoid shorting.
Fig.1 Circuit Diagram of HF Push Pull PA
Fig.2 PCB layout of HF Push Pull PA
HF Power Amplifiers
Fig.3 VU2VKC's RF. PA STAGE
Fig.4 VU2VJY's RF. PA STAGE