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The main person behind that effort, as far as I know, is Mike Stewart, and there is an excellent video of him working on restoring original AGC hardware.

https://www.youtube.com/watch?v=2KSahAoOLdU

https://www.capellaspace.com/meet-mike-stewart-a-capella-fli...

https://thenewstack.io/how-a-programmer-recreated-apollo-10s...

https://github.com/virtualagc

This youtube series of video, follow a group that restored an Apollo Guidance Computer that a collector basically pulled from the trash.

https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

My favorite part is when they needed the version of the software that was used for the moon landing but they only had the source code for a previous version (scanned from giant binder) and the hash value of the version of the landing. By a series of educated guesses, by reading memos and by analysis of the source code they modified the old code the exact way so it gave them the correct hash, confirming that they correctly and exactly recreated the original code.

It's being a while and I go from memory, I might have some details wrong. See this video for this story. https://www.youtube.com/watch?v=-JTa1RQxU04

My new favorite YouTuber, CuriousMarc, has a whole series of videos about restoring the Apollo Guidance Computer (AGC).

His AGC Playlist: https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

His channel is full of fascinating retro-computing and EE videos.

⬐ TheDesolate0

the audio is often so bad tho, I can't understand what they are saying half the time.

⬐ kens

Just to keep everything straight, the AGC that we restored is a totally different computer from the LVDC/LVDA that this board is from. The AGCs were on the Command Module and the Lunar Module that went to the Moon's surface, while the LVDC was onboard the Saturn V rocket.

The AGC was one of the very first computers to use integrated circuits, while the LVDC used hybrid modules. The LVDC used triple-redundant circuits with voting while the AGC was not redundant. The LVDC was a 26-bit serial computer, while the AGC was a 15-bit computer. The LVDC was built by IBM, while the AGC was built by MIT and Raytheon.

It's interesting that the two computers were different in so many ways.

If you haven't seen this already, CuriousMarc has also done this awesome series on the restoration of an original AGC - Apollo Guidance Computer last year.

https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

And then there are real treats such as the restoration of a Teletype 33 ASR:

https://www.youtube.com/watch?v=QzfjT1mCRww&list=PL-_93BVApb...

Or them trying to get Fortran to compile on an IBM 1401 Mainframe dated 1959. https://www.youtube.com/watch?v=uFQ3sajIdaM

I love his videos he has a webpage with merch if you want to support him https://www.curiousmarc.com/

If you are new to his channel I cannot recommend enough the Apollo AGC videos https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

Don is still around, and is still awesome! His memory for events around that time is surprisingly sharp, for it being 50 years ago.

He's been an invaluable resource for us at the VirtualAGC project [1]. He provided over half (!) of the AGC programs we've made available, including LM software for Apollo 5, 9, 10, 11, 12, 13, and 15-17, plus several other ground development programs. He also was the source of a majority of the schematics that we used in the AGC restoration [2] -- I can say with 100% confidence that it wouldn't have been possible to get that computer working again without his help.

He's got a book out now, Sunburst and Luminary [3], that is very good and goes into a lot of technical detail on the LM software, without getting too much into the weeds. I highly recommend it if you're interested in that sort of thing!

[1] http://www.ibiblio.org/apollo/

[2] https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

[3] https://www.sunburstandluminary.com/SLhome.html

⬐ js2

HN, if nothing else, look through the photos and captions:

https://www.sunburstandluminary.com/SLgallery.html

⬐ Quai

Such impressive work, in so many ways. The amount of knowledge and expertise you guys brought to the project is immense!

⬐ zweizeichen

Mike, thanks a lot for working on the restoration project! It was amazing to watch your progress and the ingenious tools and solutions you guys came up with. It also sparked my interest in AGC-related things and while I at first expected it to be a somewhat simple and elegant machine (easier to formally verify) I quickly realized it too like almost any engineering project was subject to reality/deadline-driven compromises everywhere (looking at you memory architecture). However, it is a machine which still 'fits in your head' compared to the historical achievement. We probably won't be able to do that kind of thing with the more recently developed, more complex systems we're going to use for the next steps in space exploration.

Not so much an article about the 50th anniversary, but just the main article about Apollo 11.

If you are into space stuff, and haven't seen it yet, there were some pretty cool projects going on on Youtube in preparation for the 50th anniversary:

- CuriousMarc's restoration series of an actual ACG [0]

- Applied Science made a replica DSKY electroluminescent glass panel display [1]

- Project Egress: A maker collaboration on building a replica of the Apollo 11 door (Adam Savage, Jimmy Diresta, This old tony, Blondihacks, etc) [2]

[0] https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb... [1] https://www.youtube.com/watch?v=Z2o_Sp2-aBo [2] https://www.youtube.com/results?search_query=%23projectegres...

CuriousMarc's Apollo Guidance Computer (AGC) restoration is a must-watch: https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

⬐ acomjean

I’ll second that. I particularly liked the part on home the memory worked

⬐ SpikeDad

I'm amazed at the technical skill and knowledge he and his team has. Fabricating simulations, replacement parts, unpotting modules and repairing them, etc, etc, etc.

I thought the Xerox Alto restoration was amazing - this beats it handily.

CuriousMarc's series on the AGC restoration has been really cool to watch: https://www.youtube.com/watch?v=2KSahAoOLdU&list=PL-_93BVApb...

there is a youtube channel trying to rebuild the apollo launch computer.

Very nerdy. The memory is rings of magnets. It is pretty fun though:

https://www.youtube.com/watch?v=2KSahAoOLdU

And here is some excellent footage of the restauration of a real AGC: https://youtu.be/2KSahAoOLdU

Ongoing effort of restoring an AGC

First episode: https://www.youtube.com/watch?v=2KSahAoOLdU

Restoring original Apollo AGC

https://www.youtube.com/watch?v=2KSahAoOLdU&index=1&list=PL-...

⬐ alwaysreading

So cool, thank you for sharing. The modular design of the AGC is really nice.

⬐ Xibur

It is great to hear that the efforts of the different team members are brought together and to see the progress. Absolutely fascinating how the dedication of a few engineers can bring history to life.

We are [re]living in exciting times!

If you are interested to see more of the groundwork, a few weeks back on the HN front page we had the link to the engineer working on the Rope Memory Modules (effectively the ROM). His channel has the "unboxing" video of the AGC that is currently in the process of being restored: https://www.youtube.com/watch?v=OkFy30kxfh4

*edit fix typo

⬐ theclaw

This is amazing to see - completely unpotted AGC! I've been following Curiousmarc's channel for a while and it's great to see this. Anyone interested in AGC stuff might also want to check out this video from the 34th Chaos Communication Congress that exhaustively explains how it works: https://www.youtube.com/watch?v=xx7Lfh5SKUQ