BPI means bits per inch and specifies the data density a magnetic coil can hold.
These are magnetic coil bands designed by IBM with 6250 BPI. BPI means bits per inch and specifies the data density a magnetic coil can hold.
These are magnetic coil bands designed by IBM with 6250 BPI. BPI means bits per inch and specifies the data density a magnetic coil can hold.
9-Track Tape Reel.
It occupies a quad-width, double-height flipchip board you can visually read off its contents (presence or absence of diodes). In its time it represented a giant leap forward since you no longer had to toggle the bootstrap in on the frontpanel switches.
This particular object was used up until 2012 in the Data Centre. It slots into one of the Disk Server trays. Hard disks were invented in the 1950s. They started as large disks up to 20 inches in diameter holding just a few megabytes (link is external). They were originally called "fixed disks" or "Winchesters" (a code name used for a popular IBM product). They later became known as "hard disks" to distinguish them from "floppy disks (link is external)." Hard disks have a hard platter that holds the magnetic medium, as opposed to the flexible plastic film found in tapes and floppies.
With arrival of CDC 6600 at CERN in January 1965, there came the first half-inch wide 7-tracks tape units with magnetic tapes at recording densities of 200, 556 and 800 bpi (bytes per inch).
10BASE5 Thick Ethernet Cable, 10Mbit/sec. In the 1980s and early 1990's, Ethernet became more popular and provided a much faster data transmission rate. This cable is one of the first ethernet cables from 1983, a thick, bulky affair. Computers were attached via "Vampire Taps" which were connectors screwed straight through the shielding of the cable.
This magnetic disk was one of three which interfaced with various Control Data machines. This single platter came from a Control Data 7638 Disk Storage Subsystem and could contain up to 10MB - about the size of a few MP4's on your iPod.