In the development of this power amplifier, the basic scheme YU1AW was used with small corrections (pic. 1).    
            When I testing  linear power amplifier, the anode voltage was 2.000 V, the anode current was about 0.5 A,
            and the grid current about 70 mA. The amplifier was powered with 20-25 W, so I got about 500 W at the output.
            After that, I increased the input power and I got about 750 W at the output, with the allowed anode and grid current.
            That is maximum power of this amplifier. I think that 600-650 W is optimal power for long life of tubes.
            I didn't have a suitable antenna relay, so I made it from two ordinary relays with gold plated contacts and placed it
            in a copper box in which I made partitions to separate the input and output (pic. 15 - 18).