Core Memory Photo Gallery by jimhwy at pbase.com

Core Memory

Control Data core memory module.

This is a core memory module from a Control Data computer ca. 1966. Years ago, probably in the late '70s or early '80s, the company I worked for was asked to remove this computer from its location in an office within a bank building. The machine needed to be removed to free up valuable space since it was being replaced by the very modern DEC PDP-11.

Instead of filling a room, the new computer fit neatly into one tall 19" rack.

In order that the other bank tenants and customers not be disturbed, we were instructed to cut up the old computer with oxy-acetylene torches if need be so that it could be shoved out a 2nd story window and into the waiting dump truck bound for the landfill.

Needless to say, a bunch of nerds such as us were unable to trash a lot of the prime parts from this beast and they ended up in various peoples' garages, homes, and actually back at our office.

One of the bits I salvaged was this core memory module. I hate to imagine what it cost new.

I was reminded of it a while ago when another photographer posted a photo of some other core memory.

I naturally figured I should take the time to make a few photos of this amazing piece of computing history.

IMG_3456small.jpg	IMG_3436small.jpg	IMG_3437small.jpg	IMG_3452small.jpg
IMG_3451small.jpg	IMG_3450small.jpg	IMG_3449small.jpg	IMG_3448small.jpg
IMG_3447small.jpg	IMG_3455small.jpg	IMG_3485-small.jpg	IMG_3491-crop1-medium.jpg
IMG_3498-crop-small.jpg	IMG_3498-small.jpg

comment |

Anurag		24-Oct-2022 02:34
computer memory allocation, since the DOS executable is programmed at a higher level in the operating system executable is programmed at a higher level in the operating system the fact that data in an application is written to disk and retrieved as needed to be used The IDE handles all the coding, editing, code management, and even debugging, but the program still needs a server to load the data, find out https://olevel.in

Guest		24-Oct-2022 02:32
computer memory allocation, since the DOS executable is programmed at a higher level in the operating system executable is programmed at a higher level in the operating system the fact that data in an application is written to disk and retrieved as needed to be used The IDE handles all the coding, editing, code management, and even debugging, but the program still needs a server to load the data, find out Olevel

Anurag		24-Oct-2022 02:32
computer memory allocation, since the DOS executable is programmed at a higher level in the operating system executable is programmed at a higher level in the operating system the fact that data in an application is written to disk and retrieved as needed to be used The IDE handles all the coding, editing, code management, and even debugging, but the program still needs a server to load the data, find out Olevel

cbcalvin		10-Feb-2014 23:11
In 1973-74 I was a sysadmin/Computer Operator for a Hewlett-Packard Time-Shared BASIC system. HP 2115 and HP 2116 processors, Vermont Memory drum. Core memory. From time to time the system would freeze. The first thing that we would try was to power off/power on the processor. With core memory, it forgot nothing but coming out of power-up, it would retry the operation at the stored instruction counter. About a 70% success rate. Saved a 25 minute reload from mylar punched tape.

jimhwy		10-Aug-2012 01:29
As for the cores clattering and such. I remember being told by a guy who worked for Control Data Corp. that one of their huge breakthroughs, which they kept secret, was when someone at CDC figured out that you could "thin" RTV (silicone sealant) and then dip the cores in it. It soaked in and dampened mechanical vibrations in the cores without altering their magnetic properties. And that, supposedly, allowed them to run the memory faster than the competition. I hope I'm not giving up an important trade secret by mentioning that! :)

Amando		31-Aug-2007 11:23
Absolutely beatiful!! Nice ferrite memory modules, the last time a bit of random access memory could be seen by human eyes. Thanks for sharing

Mark McAtee		21-Sep-2006 02:28
Leave it to James to use a ruler with tenths/hundredths of inches rather than something normal to most of us outside. Last time I saw one of those it was used to set the ring gap on an old Harley (that all the closer HD got. cool ferrite rings though. I think I'll try to find a supplier.

eJohn Waldron		20-May-2006 16:34
It's interesting to see just how far we have progressed. Yet compaired with biological memory we still have a very long way to go.

Guest		18-May-2006 17:36
I remember seeing similar stuf a few years later (mid-1970's) where the circuit boards were huge and had big components. I used to save a few such items but unfortunately during several moves I was convinced to toss them away. Excellent pictures and thanks for the memories! Andy K.

jCross		17-May-2006 16:46
Cool. I haven't seen one of these in years. I was once told you could hear the little cores clatter when they were energised. This might be a very early one, because I believe they became quite compact (for core anyway) with development. John

click on thumbnails for full image

Type your message and click Add Comment

It is best to login or register first but you may post as a guest. Enter an optional name and contact email address. Name
Name Email
help	private comment