The Sony PD-1 (also labelled as 2inch DataDisk) was a floppy disk design introduced in 1987 for the Sony PJ-100 Personal Word Processor (labelled as ‘Produce’). This was a portable word processor that incorporated a detachable dot-matrix printer.
The PD-1 disk used the same form-factor as Sony’s Video Floppy, and in fact the PD-1 has the VF logo stamped into the shell. The PD-1 was purely for data storage, and could store 47 documents when used with the PJ-100. By contrast, a Video Floppy stored 50 analogue video stills. Sony claimed a capacity of 1 MB for the disk, but it’s unclear if this could all be used effectively if there was a limitation on the number of files.
Sony later released a second model of Personal Word Processor using the PD-1 disc, the PJ-1000, in 1989. This claimed to store 60 documents on the disk, or 170 A4 pages of text.
A similar but incompatible version of the 2-inch floppy disk (called LT-1) could be formatted for 720 KB of data, and in this form was used in the Zenith Minisport laptop computer circa 1989.
Dimensions: 60 mm × 54.1 mm × 3.5 mm
Capacity: 1 MB