The dim doctor again, here. I think I understand a bit better now.
Might I suggest that the fft code added could produce a very useful narrow band spectrum analyser feature to the Nano, with a narrower minimum resolution bandwidth than the Tinysa.
Yes there might be odd spurs which would have to be sorted out by the operator, perhaps by a tiny frequency change of the signal being examined, or a nudge to the centre frequency of the Nano. But that is half the fun for us hobbyists, especially if one has access to resolution bandwiths otherwise only available on very expensive kit, or cobbling up a sdr dongle into a compurer somehow ( I have managed to display ¡°apparent¡± resolution bandwidths of 10hz using a rsp1 sdr box - I do not know if it was real, but it looked impressive on the computer screen).
At ?50, special firmware on a dedicated extra Nano (I already have two) just for very narrow rbw would be worth having. I presume the minimum useful rbw would be limited by the device¡¯s phase noise of the various oscillators.
Steve L. G7PSZ
