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No, the Apollo Guidance Computer block I also used integrated circuits: 4100 3-input NOR gates according to Eldon Hall's book. It's a bit murky what computer wa

by kens 3y ago

No, the Apollo Guidance Computer block I also used integrated circuits: 4100 3-input NOR gates according to Eldon Hall's book. It's a bit murky what computer was the first to use ICs. Texas Instruments built the Semiconductor Network Computer in 1961, calling it "molecular electronics" or "Mol-E-Com". The AC Spark Plug MAGIC and Martin MARTAC 420 development started in 1961. The Minuteman II computer (Autonetics D37C) started in 1962. For more see https://www.computerhistory.org/siliconengine/aerospace-systems-are-first-the-applications-for-ics-in-computers/ https://www.computerhistory.org/siliconengine/aerospace-syst...

pfdietz 3y ago
That is contradicted by this source: https://ntrs.nasa.gov/api/citations/19880069935/downloads/19880069935.pdf https://ntrs.nasa.gov/api/citations/19880069935/downloads/19... "Block I was basically the same technology as the Polaris system. Block II incorporated new technology within the original architecture." "The most important reason for going to Block II was the availability of new technology. The Block I design used core transistor logic. It had several disadvantages: [...] These disadvantages led MIT to being studying, as early as 1962, the possible use of integrated circuits (ICs) to replace core transistor circuits."
- kens 3y ago
  Your source is slightly confused. The original design of the Apollo Guidance Computer used core-transistor logic and they built three prototypes 1A, 1B, and 3C in large racks. In 1962, they switched to integrated circuits and built rack-mounted IC prototypes (AGC3 and AGC4) using Fairchild Micrologic. They built the Block I AGC systems starting in 1963 and launched one on an unmanned flight in 1966. Block II planning started in 1963 with qualification tests in 1966. All crewed flights used Block II systems. Source: "Journey to the Moon" by Eldon Hall, designer of the AGC. TL;DR: the core-transistor logic AGCs were prototypes before Block I; Block I used ICs. You can see a photo of a Block I module with flat-pack ICs here: https://www.computerhistory.org/revolution/digital-logic/12/278/1441 https://www.computerhistory.org/revolution/digital-logic/12/...
  - pfdietz 3y ago
    That clears it up. My source appears to be in error, then. Thanks.

by kens 3y ago

pfdietz 3y ago

That is contradicted by this source: https://ntrs.nasa.gov/api/citations/19880069935/downloads/19880069935.pdf https://ntrs.nasa.gov/api/citations/19880069935/downloads/19... "Block I was basically the same technology as the Polaris system. Block II incorporated new technology within the original architecture." "The most important reason for going to Block II was the availability of new technology. The Block I design used core transistor logic. It had several disadvantages: [...] These disadvantages led MIT to being studying, as early as 1962, the possible use of integrated circuits (ICs) to replace core transistor circuits."

kens 3y ago
Your source is slightly confused. The original design of the Apollo Guidance Computer used core-transistor logic and they built three prototypes 1A, 1B, and 3C in large racks. In 1962, they switched to integrated circuits and built rack-mounted IC prototypes (AGC3 and AGC4) using Fairchild Micrologic. They built the Block I AGC systems starting in 1963 and launched one on an unmanned flight in 1966. Block II planning started in 1963 with qualification tests in 1966. All crewed flights used Block II systems. Source: "Journey to the Moon" by Eldon Hall, designer of the AGC. TL;DR: the core-transistor logic AGCs were prototypes before Block I; Block I used ICs. You can see a photo of a Block I module with flat-pack ICs here: https://www.computerhistory.org/revolution/digital-logic/12/278/1441 https://www.computerhistory.org/revolution/digital-logic/12/...
- pfdietz 3y ago
  That clears it up. My source appears to be in error, then. Thanks.