Uploaded October 2023 | Updated September 2026, 1 week ago
Core Rope Memory, which contained the programs that landed man on the Moon in the 1960s, is insanely complicated. But that won't stop Mike from making a custom reader for it, so he can recover Apollo Guidance Computer programs lost to history.
Mike Stewart's Core Rope Visualizer: http://apolloguidance.computer/rope/
Apollo Guidance Computer Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59FWrLZfdlisi_x7-Ut_-w7
Core Memory Videos:
youtu.be/AwsInQLmjXc
youtu.be/7ozNMgx7WtQ
youtu.be/e9ih93tuH1k
Look Mum No Computer Core Rope Drum Machine: youtu.be/zytjONYkU94
Mike's Electric Stuff Soviet Dialer: youtu.be/tPT6nIRFI_I
Stuff that supports the channel:
- Amazon links for the tools I use in the lab (supports the channel if you buy from there)
curiousmarc.com/amazon-links
- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store
- Support us on Patreon: patreon.com/curiousmarc
Our lovely sponsors
- PCBWay: fast turn PCBs, pcbway.com
- Electro-Rent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
- R&D Microwaves: rdmicrowaves.com
Get more technical info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about
00:00 Intro: Apollo Guidance Computer restoration
02:21 What is core rope memory?
05:16 Previous core rope recoveries with our AGC
06:44 Our AGC is sold at auction
07:36 Mike's core rope reader prototype
11:09 Last minute core rope "hack" for Apollo 11
14:04 Software recovered so far
14:48 Trying the reader for the first time and error
17:56 Core rope explanation: data encoding
20:13 Transformer rope is not core rope
21:24 Core rope explanation: reading using bistable cores
26:09 Core rope explanation: molybdenum permalloy cores
28:22 Experimental demo of moly cores
31:49 Core rope explanation: addressing with inhibits
33:59 Apollo core rope simulator, inhibit wires
35:56 Set and reset wires
37:45 Parity wires and the design error
45:02 Mike fixes the reader and tries again
47:38 Success! Congrats Mike!
Core Rope Memory, which contained the programs that landed man on the Moon in the 1960s, is insanely complicated. But that won't stop Mike from making a custom reader for it, so he can recover Apollo Guidance Computer programs lost to history.
Mike Stewart's Core Rope Visualizer: http://apolloguidance.computer/rope/
Apollo Guidance Computer Restoration Playlist: youtube.com/playlist?list=PL-_93BVApb59FWrLZfdlisi_x7-Ut_-w7
Core Memory Videos:
youtu.be/AwsInQLmjXc
youtu.be/7ozNMgx7WtQ
youtu.be/e9ih93tuH1k
Look Mum No Computer Core Rope Drum Machine: youtu.be/zytjONYkU94
Mike's Electric Stuff Soviet Dialer: youtu.be/tPT6nIRFI_I
Stuff that supports the channel:
- Amazon links for the tools I use in the lab (supports the channel if you buy from there)
curiousmarc.com/amazon-links
- Channel merch on Teespring: teespring.com/stores/curiousmarcs-store
- Support us on Patreon: patreon.com/curiousmarc
Our lovely sponsors
- PCBWay: fast turn PCBs, pcbway.com
- Electro-Rent: electrorent.com
- Keysight: test instruments: keysight.com
- Samtec: connectors: samtec.com
- R&D Microwaves: rdmicrowaves.com
Get more technical info on the companion site: curiousmarc.com
Contact info: youtube.com/curiousmarc/about
00:00 Intro: Apollo Guidance Computer restoration
02:21 What is core rope memory?
05:16 Previous core rope recoveries with our AGC
06:44 Our AGC is sold at auction
07:36 Mike's core rope reader prototype
11:09 Last minute core rope "hack" for Apollo 11
14:04 Software recovered so far
14:48 Trying the reader for the first time and error
17:56 Core rope explanation: data encoding
20:13 Transformer rope is not core rope
21:24 Core rope explanation: reading using bistable cores
26:09 Core rope explanation: molybdenum permalloy cores
28:22 Experimental demo of moly cores
31:49 Core rope explanation: addressing with inhibits
33:59 Apollo core rope simulator, inhibit wires
35:56 Set and reset wires
37:45 Parity wires and the design error
45:02 Mike fixes the reader and tries again
47:38 Success! Congrats Mike!
