Saturn V Memory Module

The Launch Vehicle Digital Computer autopiloted the Saturn V rocket from launch through Earth orbit during the Apollo Moon mission. Because semiconductors were not available until the 1970s, the Saturn V Memory Module relied on random access magnetic core technology.

This is a very rare artifact. Not only were they expensive to build and thus manufactured in limited quantities,  once the Saturn V booster rockets burned through their fuel, therewere jettisoned and ended up at the bottom of the ocean. This module is one of the few spares.

Core memory used small ferrite rings to store one bit in each core through magnetization created when current was sent through wires within and around the core. Reading the contents of a given memory address created current in a wire corresponding to that address. Each address wire was woven either through a core to signify a binary (1), or outside of the core, for a binary (0).

The lower half of the computer was filled by up to 8 core memory modules. This allowed the computer to hold a total of 32 kilowords of 26-bit words.