MYSTERY PHOTO

Who are these people and what computer is that?

Take your best guess! The first three Core readers who submit correct answers after July 1, 2007, will receive a free copy of Core Memory: A Visual Survey of Vintage Computers.

The fourth and fifth correct submissions will receive Computer History Museum posters.
Email your guess to: editor@computerhistory.org.

Good luck!

LAST ISSUES MYSTERY ITEM ANSWER

Last issue’s mystery item was a rope memory unit from the Apollo Guidance Computer. Congratulations to Brian Knittel, Mike Albaugh, and Randy Neff for correctly identifying it. Each of these lucky people will receive a “25th Anniversary of the Microprocessor” poster.

Rope memory is a special form of magnetic core memory (“core”). While core is useful for storing temporary or changing results, rope memory is a form of read-only memory (ROM) that will keep its contents even in the absence of power. This quality made it particularly attractive as a means of storing the various control programs for the Apollo spaceflight. It was also a very dense form of memory, though brittle and extremely difficult to manufacture. This particular unit was made by Burroughs.