Electronic computers offered unprecedented speed. But mechanical memory—slowed by moving parts—was a nagging speed bump.
The Williams-Kilburn tube, tested in 1947, offered a solution. This first high-speed, entirely electronic memory used a cathode ray tube (as in a TV) to store bits as dots on the screen’s surface. Each dot lasted a fraction of a second before fading, and a mechanism was incorporated for automatically refreshing these dots.
Its roots stretched back to 1946, when British researcher F.C. Williams saw cathode ray tube storage at MIT, in an extension of the wartime radar work on permanent echo cancellation. Williams saw that the basic problem was charge decay, and he decided to tackle this problem so that the CRT technique could be improved upon for use in computers. Ultimately, however, the unreliable Williams-Kilburn Tube proved a technological dead end.
F.C. Williams was a true example of the British 'string and sealing wax' inventive genius, who had built a primitive electronic computer out of surplus World War II radar parts strictly on his own inspiration….
The 701 was IBM’s first commercial digital electronic computer. Its unreliable Williams-Kilburn tube memory caused an average time-to-failure of about 15 minutes.View Artifact Detail
Inventors of the Williams-Kilburn tube, Tom Kilburn (left) and Freddie Williams (right), pose in front of the Manchester Mark I computer. This early random-access memory was used in several early computers.View Artifact Detail
A close-up view reveals dots (ones) and spaces (zeroes) on the face of a tube. The bits had to be refreshed before the dots faded, in less than a second.View Artifact Detail