Spectran Beta 4 has some limitations, that will be taken care of in the final release.
Let's see them one by one :
 

• Moon : the program has provision for displaying the Moon azimuth and zenit, but it has not been implemented yet.
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• Signal-to-noise ratio : it has been asked for, and it will be probably implemented in one of the next releases.

          WAV files writing and reading is planned, but not implemented yet

• Many other limitation that you will discover yourself when running the program. Bear with us : this is only a beta...