3 1/2" 720K Disk Drive Conversion

A conversion putting a 720K 3.5-inch drive on the ADAM - four and a half times what the machine's own 5.25-inch drive holds, on media in a hard shell that survives handling.

Why it mattered

• The ADAM shipped with 160K single-sided drives and 256K data packs.
• 720K is the standard PC double-density format, so disks stayed cheap and obtainable long after 5.25-inch stock had gone.

An ADAMnet drive carries its own processor and answers commands on the bus, so a conversion is firmware as much as mechanism. E&T Software sold a 3.5-inch conversion too, and Micro Innovations built 720K drives outright - three companies, three approaches, all catalogued here.