Amazing! I was thinking like about washing machine sized for 32k...
I dont quite understand how the X and Y wires work.
What speed can it run at? How much heat might the AT motherboard
sized setup give off?
Sounds like that's the sort of RAM I should have in my car...it will
give a computer error every blue moon, which requires a restart of
the engine AFAIK.
Can the sense wires be made of gold?
On Tuesday, "John P. Tomany" <[EMAIL PROTECTED]> typed:
] Just a little bit more about CORE memory...
]
] The actual cores were tiny ferrite rings, strung on extremely
] thin wire. ( Think of the small grain-of-wheat plastic beads
] that kids used to string onto #30AWG wire as part of an "arts
] and crafts" project; these were just a bit bigger than memory
] cores.)
]
] The things would be physically laid out in an X/Y (or row-and-
] column) pattern. In one type, a wire would be passed through
] every core on a single row. Another wire would be passed through
] the column. This would be repeated for each row and column,
] forming the address lines. By passing HALF the current necessary
] ( to "change" a core's magnetic field ) through both of these
] row and column address lines, only the one core which received
] both "halves" of the current would switch magnetic fields.
]
] The change was sensed by a single wire which ran through every
] core on the (core) plane. It usually was routed down one column,
] up the next, down the third column, etc....
]
] One very high-security access system I maintained in 1972 used
] a core plane about the same size and shape as an AT motherboard.
] It was 1024x1 ram - and the system had 16 of them. A year later,
] these were replaced by four 1024x4 cores, each of which was housed
] in a metal box about the size of a parallel Zip drive.
] By 1976, the airborne ones in the F-4E/G aircraft ( where size and
] weight is always a consideration ) packed 32k x 12 into a metal-
] encased card about the same dimensions as a "baby AT" motherboard,
] but 3/4 in. (2 cm) thick. These are still flying today ( as QF-4s)
] and were the "unsung heroes" of the 1990/91 Gulf War. ( F-4G "Wild
] Weasel" SAM-killers preceeded the F-117 Stealths into Baghdad.)
]
] BTW - estimates for how long a core retains its "memory" are in
] excess of ten thousand years, if undisturbed. ( The sense wires
] would probably oxidize to dust by then...)
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