Time is almost up for magnetic storage from the 80s and 90s. Various physical limitations in storage methods from this era are conspiring to slowly degrade the data stored on things like tape, floppy disks, and hard disk drives, and after several decades data may not be recoverable anymore. It’s always worth trying to back it up, though, especially if you have something on your hands like critical evidence or court records on a nearly 50-year-old floppy disk last written to in 1993 using a DEC PDP-11.
This project all started when an investigation unit in Maryland approached the Bloop Museum with a request to use their antique computer resources to decode the information on a 5.25″ floppy disk. Even finding a floppy disk drive of this size is a difficult task, but this was further compounded not just by the age of the disk but that the data wasn’t encoded in the expected format. Using a GreaseWeazle controlled by a Raspberry Pi, they generated an audio file from the data on the disk to capture all available data, and then used that to work backwards to get to the usable information.
After some more trials with converting the analog information to digital and a clue that the data on the disk was not fragmented, they realized they were looking at data from a digital stenography machine and were finally able to decode it into something useful. Of course, stenography machines are dark magic in their own right so just getting this record still requires a stenographer to make much sense out of it.