I want to make a 25W HF amplifier that can handle an input up to 8W. I found a schematic by ON6MU which can handle up to 2.5W input. There is an attenuator at the input that I copy here. R3-4 is 1W, R2 and R5 are both 0.5W.
What would be needed to change this circuit to allow for an up to 8W input? Would it be enough to take an R3-4 that can handle 5W and R2 and R5 that can handle 2W, or would I need to change values as well?
How would I actually calculate this?
The attenuator should work for 17m - 80m bands.
The full schematic, for reference purposes: