Without any filter @ 28 MHZ -> Full AM audio (792 kHz AIR Pune) is replicated with high fidelity ;)
With my 3-Pole BCI filter @ 28 MHz -> FT8 traffic is heard and decoded, AM voices CANNOT be hear for the most part BUT the audio output has loud screechy, weird artifacts! It is not pleasant to listen to at all.
With professional "Morgan System SurgeStop" BPF @ 28 MHz -> The loud screechy, weird audio artifacts are gone 100%! FT8 traffic is heard very clearly but the audio output is quite feeble - which is totally fine as we just need to amplify the audio output more.
With professional "Morgan System SurgeStop" BCI filter (3.5 MHz model), we can still hear the loud screechy, weird artifacts! Same as the 3-Pole homebrew BCI filter!
The question now is: Can the 7-pole VK3YE BCI RX filter also provide similar
receive performance as the SurgeStop BPF?
Update: With 7-pole VK3YE BCI RX filter, we still hear the loud screechy, weird audio artifacts, same as the professional "Morgan System SurgeStop" BCI filter!
Conclusion 1: BCI is not the only problem! We have other types of interferences going on - perhaps from strong shortwave station(s) it seems!
VK3YE BCI filter -> https://www.youtube.com/watch?v=fgQenFJOjr4
Conclusion 2: We surely need BPF filter bank for crystal clear audio, and high performance!