Floppy Disk Variants - 3" Diskettes: Amstrad CPC, PCW, Spectrum, etc.

3" Diskettes: Amstrad CPC, PCW, Spectrum, etc.

The 3-inch disk format was widely used by Amstrad CPC and Amstrad PCW machines, became available for Spectrum systems once Amstrad took over their manufacture, and was also adopted by some other manufacturers/systems such as the Tatung Einstein. Three-inch diskettes bear much similarity to the 3½-inch type, with some unique and somewhat curious features. One example is the rectangular-shaped plastic casing, almost taller than a 3½-inch disk, but less wide and thicker (i.e. with increased depth). The actual 3-inch magnetic-coated disk occupied less than 50% of the space inside the casing, the rest being used by the complex protection and sealing mechanisms implemented on the disks, which thus were largely responsible for the thickness, length, and relatively high costs of the 3-inch disks. On the early Amstrad machines (the CPC line and the PCW 8256), the disks were typically flipped over to change the side, as opposed to being truly double-sided. Double-sided mechanisms were introduced on the later PCW 8512 and PCW 9512, thus removing the need to remove, flip, and reinsert the disk.