core memory module, planar
Date: 1971
Inventory Number: 1997-1-1249
Classification: Computer
Dimensions:1.3 × 26.6 × 22.8 cm (1/2 × 10 1/2 × 9 in.)
DescriptionThe main body of the panel is rectangular and constituted of layers of conducting foil encased in textured, partially transparent grey epoxy. Along one of the long edges of the panel are four green plastic attachments. Each has a rectangular base attached directly to the edge of the panel, and a short straight stem that expands outward into a V-shaped spoke. On the other long edge of the panel are four rectangular extensions, separated by cut grooves. There are eighteen thin, exposed brass strips embedded in each rectangle for connecting the memory to other components of the computer or to other memory panels in the same stack. The brass strips are exposed on the top and bottom of the memory panel.
Here the "top panel" will refer to the side of the memory plane in which the memory grid is visible. There are seven black rectangular microchips fixed along each short edge of the panel, parallel to the long edges of the panel. There is one black rectangular microchip along each of the short edges of the panel, parallel to the short edges. There are eight black rectangular microchips along the long edge with the green plastic extensions. The outermost two on either side are parallel to the long edge of the panel. The innermost four are parallel to the short edges of the panel. The main core memory panel is centered and visible on the top panel. It is constituted of a grid of extremely fine, intersecting red wires. There is a tiny, black (probably ferrite) ring around each intersection node on the grid, making it appear dark from a distance. There are two rectangular panels in the center of the grid in which intersection nodes do not have ferrite rings around them. These panels appear red from a distance. A plexiglass rectangle is fixed in the center of the main panel by a small post at each corner. This rectangle is fixed above the core memory grid. Very thin red wires emerge from the bottom edge of this panel and attach to the exposed brass strips in the rectangular extensions along the bottom edge of the panel. The core memory is attached to other computer components and core memory panels through those wire-brass strip connections.
Various soldered connectors and soldered circuit paths are visible along the bottom panel of the memory plane. Along the left, right, and top edge there are many circular soldered connections, each one connected to one of the downward pointing pins of the microchips on the top panel. Various soldered circuit paths and connections end at the exposed brass strips on the rectangular extensions along the bottom edge. Through those brass strips, the circuits can be connected to other computer components or panels of core memory.