Some time ago I found an interesting application for radio astronomy...
http://eartoearoak.com/software/rtlsdr-scanner
It is yet another Spectrum Analyser based on RTL-SDR, GUI written in Python.
It can export scans from memory into *csv format on HD (it seems only last 500 scans?), but it can't be configured to do it without intervention and continuously, until stopped.
I contacted author (Al) today, and now I am waiting for response.
Perhaps someone from this forum could help with this in case there is nothing from authors?