Another Types of FLOPPIES

12-inch floppy disks

In the late 1970s some IBM mainframes also used a 12-inch (30 cm) floppy disk, but little information is currently available about their internal format or capacity.

4-inch floppies

IBM in the mid-80s developed a 4-inch floppy. This program was driven by aggressive cost goals, but missed the pulse of the industry. The prospective users, both inside and outside IBM, preferred standardization to what by release time were small cost reductions, and were unwilling to retool packaging, interface chips and applications for a proprietary design. The product never appeared in the light of day, and IBM wrote off several hundred million dollars of development and manufacturing facility.


Auto-loaders

IBM developed, and several companies copied, an autoloader mechanism that could load a stack of floppies one at a time into a drive unit. These were very bulky systems, and suffered from media hangups and chew-ups more than anyone liked, but they were a partial answer to replication and large removable storage needs. The smaller 5¼- and 3½-inch floppy made this a much easier technology to perfect.


Floppy mass storage

A number of companies, including IBM and Burroughs, experimented with using large numbers of unenclosed disks to create massive amounts of storage. The Burroughs system used a stack of 256 12-inch disks, spinning at high speed. The disk to be accessed was selected by using air jets to part the stack, and then a pair of heads flew over the surface as in any standard hard disk drive. This approach in some ways anticipated the Bernoulli disk technology implemented in the Iomega Bernoulli Box, but head crashes or air failures were spectacularly messy. The program did not reach production.


2-inch floppy disks
2-inch Video Floppy Disk from Canon.
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2-inch Video Floppy Disk from Canon.

A small floppy disk was also used in the late 1980s to store video information for still video cameras such as the Sony Mavica (not to be confused with current Digital Mavica models) and the Ion and Xapshot cameras from Canon. It was officially referred to as a Video Floppy (or VF for short).

VF was not a digital data format; each track on the disk stored one video field in the analog interlaced composite video format in either the North American NTSC or European PAL standard. This yielded a capacity of 25 images per disk in frame mode and 50 in field mode.

The same media was used digitally formatted - 720 kB double-sided, double-density - in the Zenith Minisport laptop computer circa 1989. Although the media exhibited nearly identical performance to the 3½-inch disks of the time, it was not successful.