The floppy drive is similar in design to the Roctec floppy drives. I have two of those, neither of which work. Mine has a three-position switch on the back as well, labeled 0, I, and II. It seemed to me like this was a drive selector. For instance, if you plugged the drive into a 2000 with one floppy, you'd have to select I to make it df1:. For a two drive 2000, you'd select II meaning df2:. 0 seemed to disable the drive.
The floppy drives in mine were made by citizen, but it looks like yours are alps. Maybe the interface and box were made by some no-name third party allowing manufacturers to throw in a floppy drive and print their name on the case.
Edit: by the way, anyone know where I can get replacement floppy drives for the broken roctec drives? Mine are probably misaligned. The floppy interface cable looks unusual, otherwise i'd plug in another drive.
brian