File:Apollo Guidance Computer (AGC).jpg

English: Apollo Guidance Computer (AGC) and Navigation System from the second Lunar Module, LM-2 with the IMU ball, cooling system and all of the interconnect.

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UPDATE: the CollectSpace community is just incredible. Overnight, they identified the Apollo Guidance Computer. Amazingly, it comes from the second Lunar Module, LM-2.... the one that is in the Smithsonian! Documentation of its history starts in 1967. The rope-core memory modules contain the Aurora program for the Apollo 14 Lunar Module where they were used for extensive testing before launch. It was listed as a flight-worthy spare for Skylab, and finally, it was used extensively at Edwards AFB with new interface modules to test the first use of digital fly-by-wire (DFBW) technology in F-8 jets in 1972, and finally implemented in the space shuttle.

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I am still doing research on this one, and it is fascinating. The Apollo Guidance Computer (AGC) is a module at the bottom of the stack on the left, revealed in comment stream below. And at minute 2 of this impromptu video, you can see the whole rig.

The program it contains is "Aurora revision 88", the final release of the Lunar Module system test program. Current belief is that this rig was used subsequently for research into F-8 Digital Fly-By-Wire control used on the Shuttle eventually (NASA summary). Thanks MStewart and Spaceaholic for help on this.

RR Auction is about to auction the first AGC ever seen for sale: "The Apollo Guidance Computer was a technical marvel: in the era of room-sized computers, NASA allocated one cubic foot on their spacecraft for the electric brain that would be responsible for guiding humans to the lunar surface and safely returning them home. It was up to the best and brightest at the MIT Instrumentation Lab to make it fit. Rather than using the large vacuum tubes or big discrete transistors typical in computers of the time, MIT engineers pioneered the application of integrated circuits—microchips—to accomplish the same task in a diminutive package. During 1963, the Instrumentation Lab consumed 60 percent of the integrated circuit production in the United States, and by 1964 Fairchild Industries had shipped more than 100,000 ICs for use in the Apollo program.

The AGC hardware was thus a combination of cutting-edge technology and old-school craftsmanship: while these innovative, mass-produced chips made their way into the AGC's logic modules, the computer's mission-critical software was stored in handmade 'rope memory,' contained inside its fixed memory modules, which could not be erased, altered, or corrupted. This rope memory required absolute precision and was sewn by workers recruited from local textile factories: copper wire was woven in and around ring-shaped magnetic cores, with each wire threaded through the core representing a binary "1," and each wire bypassing the core representing a "0." It took eight weeks for the workers to weave the memory for a single flight computer, at a cost of $15,000 per module.

Developed using a mix of assembly language and an interpreted mathematical language, the software contained on these modules was as innovative, and as important to mission success, as the pioneering hardware. Many of the design principles developed at MIT for coding the AGC became foundational to software engineering in general—particularly in the design of critical systems that rely on asynchronous software, priority scheduling, fault-tolerance, fly-by-wire capability, and human-in-the-loop decision making."

Back to my AGC, it is P/N 203993-091, S/N Ray 26.

The memory modules are: Memory B1 2003972 -011 Ray 86 Memory B2 2003972 -091 Ray 87 Memory B3 2003972 -111 Ray 115

And the memory jumper modules are 2003076 with -021 and -031, and S/N Ray 1, 2 and 5.