Upon seeing this
advertisement by Bell Laboratories for their "Twistor" form of
magnetic memory data storage in a 1958 issue of Radio News magazine, my
thought was that it was just another
flash in the pan,
so to speak, in the history of breakthrough, paradigm-changing inventions. It
was a variation of the non-volatile
memory that used sections of ferromagnetic wire twisted around copper wire
in such a way that electrical currents directed to particular intersections in
an x-y grid would cause a magnetic orientation to be set (store a bit) and a set
or read and sense wires permitted detection of the stored magnetic field to be
determined (read a bit). The Twistor was hailed as a much more manufacturable
form of the magnetic core memory, which required production workers with small
hands and finger to manually thread the x, y, read, and sense wires through a
matrix of miniature magnetic cores.
the primary manufacturing company for Bell Telephone (look at who made your old
dial and pushbutton phones), actually built an entire system in the mid 1960s
dubbed the Number One Electronic Switching System (1ESS)
around the Twistor. The Wikipedia entry for the Twistor says the
device was first introduced in 1957.
Bell Telephone Laboratories: New Twist in Memory Devices
Model (simplified) illustrates basic structure
of magnetic "Twistor" memory - magnetic and copper wires interwoven as in a window
screen. Twisted condition of the magnetic wire shifts preferred direction of magnetization
from a longitudinal to a helical path. One inch of twisted wire, thinner than a
hair, can store as much information as ten ferrite rings. "Twistor" was invented
at Bell Laboratories by Andrew Bobeck, M.S. in E.E. from Purdue University.
An ingenious new kind of magnetic memory has been developed by Bell Laboratories
scientists for the storage of digital information. Known as the "Twistor," it consists
basically of copper wires interwoven with magnetic wires to form a grid.
"Twistor" gets its name from a characteristic of wire made of magnetic material.
Torsion applied to such a wire shifts the preferred direction of magnetization from
a longitudinal to a helical path. This helical magnetization has been applied to
produce a magnetic storage device of unprecedented capacity for its size.
In a magnetic memory, information is stored by magnetizing a storage element.
In conventional memories the storage elements consist of rings of ferrite. In the
"Twistor," they consist of tiny segments of hair-thin magnetic wire. At each intersection
of the grid, one such segment is capable of storing a binary digit.
The "Twistor" is simple and economical to fabricate, and its minute energy requirements
are easily supplied by transistor circuits. Bell Laboratories engineers see important
uses for it in future telephone systems which demand the compact storage of much
information, as well as in digital computers for civilian and military applications.
Bell Telephone Laboratories
World Center of Communications Research and Development
Posted January 27, 2020