Sunburst and Luminary: Apollo "Rope" Memory, and other items of interest

 

Wow.  That is the method that they stored computer memory for the moon missions.  When they were satisfied with a program they would say it was time to "put it on the rope."  

Here's an article on the women who built the rope memory (and the integrated circuits used in Apollo). This reminded me of the women's collective in Hyderabad that "wove" the ferrite core transformers for Farhan's BITX rigs: 

https://www.sciencenews.org/article/core-memory-weavers-navajo-apollo-raytheon-computer-nasa#:~:text=Core%20memory%20used%20metal%20wires,to%20create%20a%20particular%20pattern.

Here is a Wikipedia article on core rope ROM memory with some great illustrations: 

https://en.wikipedia.org/wiki/Core_rope_memory

The Rope

Other stuff of interest that I have spotted so far in the book Sunburst and Luminary -- An Apollo Memoir by Don Eyles:  

-- Not long before the fatal Apollo 1 fire, an MIT colleague of Don Eyles had a drink with Astronaut Gus Grissom.  Grissom unloaded about the poor state of the spacecraft, saying that, "What we have here is a Heathkit."  Grissom died in the fire. 

-- Eyles mentions the use of 6L6 tubes in analog audio amplifiers. 

-- MIT's Doc Draper used a Minox camera.  

-- When the Apollo 11 astronauts came back and were living for two weeks in an isolation chamber, NASA had bulldozers on standby to bury the whole thing ("astronauts, staff and all") in case some dangerous moon bug was detected.  (Is that true?) 

-- At one point soon before an important missile test, engineers realized that they needed an isolation transformer.  They did not have enough time to order one.  So they took an isolation transformer out of one of their soldering stations and used it in the missile.  It worked. Sometimes you just use what you have on hand. 

CuriousMarc Gets an Apollo DSKY Running. FPGA AGC Computer. Rope Memory.

I really liked this video.  So much amazing wizardry in it.  Just the FPGA Apollo AGC simulator that Mike whipped up.  Wow.  Kudos!  

Their occassional references to "rope" brought back fond memories of "Sunburst and Luminary" by Don Eyles:  https://soldersmoke.blogspot.com/search?q=Apollo+rope 

Apollo Core Rope Memory -- CuriousMarc Takes it on (video)

Here is another amazing Apollo video from CuriousMarc (AJ6JV).  Thanks to Bob KD4EBM for alerting me to this. We have recently been discussing the "Apollo rope memory" as I read Sunburst and Luminary by Don Eyles (ex K4ZHF). In this video Marc and his colleague Mike get ahold of some actual Apollo memory modules, develop a device that allows them to read it,  and they discover a design error.  Wow.  

My analog HDR head hurts after watching this.  Even Marc says he was approaching his limits in explaining all this.  

I had not heard of the bug they discovered in the Apollo 11 software just a month before launch, and how they had to climb into the Saturn V to fix it.  Amazing.  

Thanks Marc, thanks Mike and thanks Bob.