The thickness of the magnetic layer of the disk
Removable magnetic media, manufactured by Iomega for Bernoulli drives, were extremely durable and reliable and cost quite a bit.
The special 3-inch disks used in Zip are very similar to regular floppy disks (the only significant difference is the cartridge thickness – about 1.5 times more than in FDD), and have the same disadvantages as regular floppy disks. wheels. However, on approximately the same area of the magnetic medium, an amount of information is stored that exceeds the floppy disk volume by more than 69 times!
It is known that the thinner the magnetic layer, the less adjacent areas of the disk affect each other. Therefore, thin magnetic coated discs can accumulate much more data per inch without deterioration.
Zip discs use thin magnetic coatings with high coercive force (coercive force indicates the field strength required to overwrite data on a disc). The reasons for using such coatings are quite simple.
When developing high-density drives, engineers found that at high density magnetic domains with low coercive force, the influence of neighboring magnetic domains on each other manifests itself, and the polarity of the domains changes. Data recorded at high densities began to erase themselves.
The very thin magnetic layer used in Zip disks due to the reasons already discussed above is quickly erased (remember frequent encounters with dust particles contaminated with heads), which leads not only to loss of information, but also to cartridge failure. Naturally, if the device is designed to store data, then such consequences often turn out to be disastrous.
Like FDDs, Zip cartridges can be damaged:
exposure to magnetic fields;
deformation due to overheating of the cartridge (in the sun or close to heat sources) (see Fig. 1);
mechanical impact on the surface of the disk (touching with your fingers, bending the diskette, writing on the label with a ballpoint pen);
But Zip cartridges are not only threatened by the reasons described above. The main reason for the failure of Zip cartridges in recent years have become the so-called “Death Clicks.”