James Moritz wrote:

Dear Andy & Group,
        With a 1Hz Bandwidth, isn't it rather difficult to find the signals
in the first place? How do you tell if what you are receiving is a
signal or not? It seems to me that some radically different
operating procedures will have to be devised to exploit extreme
narrow band techniques such as these!

The final version of Spectran will have audio filtering, as in Hamview.
With this, you can apply a very narrow filter to incoming audio by
just pointing with the mouse to the desired trace on the waterfall.

Hamview has a choice of both FIR and IIR filters, and probably
also Spectran will.

Alberto,   I2PHD