Build your own Apollo Guidance Computer
Would you like to build the Guidance Computer Neil Armstrong used to land on the moon in 1969?
John Pultorak did just that! He created a working reproduction of the Apollo Guidance Computer (AGC). He then wrote a complete manual that allows you to build your own copy and released it on the Internet
John Pultorak, is a Lockheed Martin software engineer and at the age of 54, built his own Apollo Guidance system in his basement.It took him four years to build it and he spent about $3, 000 for the hardware. If that wasn’t enough he then wrote a massive 1,000 page long set of documents that includes detailed descriptions and all schematics needed for anyone to build their own unit.
He says: “This report describes my successful project to build a working reproduction of the 1964 prototype for the Block I Apollo Guidance Computer. The AGC is the flight computer for the Apollo moon landings, and is the world’s first integrated circuit computer….. If you like, you can build one too. It will take you less time, and yours will be better than mine.”
He documented the project in 9 separate .pdf files:
Why build an AGC?
John Pultorak says: “Early computers are interesting. Because they’re simple, you can (if you like) actually understand the entire computer, from hardware to software. The AGC is the most interesting early computer because: a) it flew the first men to the moon; and b) it’s the world’s first integrated circuit (IC, or microchip) computer. It also has interesting architectural features.”
This was state of the art at the time. It also gave a few people the scare of their lives when the LEM was starting its descent and the AGC display stopped processing data.
The fault was sent to the backroom guys who quickly ascertained that it was just overloaded and would kick back in shortly and the mission was told to proceed. Luckily it did just that and Armstrong made his successful descent with one more heart stopping moment yet to come. It was the low fuel situation caused by the craters and boulders in the path of where the LEM was trying to land. Armstrong took control and landed the LEM away from the rocks and craters.