I tried to make the real noise floor far below the quantization noise but as suggested by xavier this is troublesome for the internal decimation in the DDC because you already are at the bottom end precision of the 8 bit sample . When I did the test again with high RF gain I finally saw the desired gain going from 2 . 4 Msps to 0 . 24 Msps . The gain from the FFT bin is working in every case . What I was looking for was to quantify the gain from DDC downconvertion and explain why I was not seeing it . But at this moment I think to have figured it out thank to all your comment about the paper , I know that one , I just read it these days . <| sep |> This commercial blows . Gtfo <| sep |> Can you timecode this for us ? I don ' t remember seeing it .