Dense disc (Jun, 1979)
“Unconventional” recording formats make recovering data from old disks a bit tricky. A problem the Archive Team has been dealing with as they endeavor to preserve roughly everything that has ever been stored. Ever.

Dense disc
The MD-4 computer mini-disc unit from IMSAI (14860 Wicks Blvd., San Leandro, Calif. 94577) uses conventional Micropolis drives, but unconventional 1024-byte-per-sector recording format. Result: an 18-percent—780K bytes-increase in storage capability. It’s $1995 with MDOS and controller.
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