Real "Core" memory

Years ago I bought an 8k card of core memory. I recently reattached it to the back of a shadow box and thought some might enjoy seeing single bits of memory. If I remember correctly standard core memory had 3 wires going thru the “donut”: 1 to read, 1 to write and 1 to clear. Anyway, here’s some pictures of ancient computer memory.


Do you think the void sticker still applies?


Interesting that this one is HP branded. I’ve seen the similar ones that DEC used which are also represented in several computer museums.

Do you know what piece of HP equipment it was used in?


Unfortunately I don’t know anything about it.

Can you imagine having the job of threading those wires? That’s the thing that always comes to my mind when I look at it. Well, that and how far technology has come.


Handweavers were in charge of teaching those skills in the beginning. It’s amazing how much influence the making of textiles and textile good have on other industries and trade.


Is that 8 kilobytes or?

Yeah, I believe 8 kilobytes. I notice that it actually says “8k x 17” but 136k seems like it would be a weird configuration so I’m not sure what to think.


Using one of the numbers visible on the PCB, I believe that this board was used in the systems described here: HP 21xx - 2116 Processors

The capacity would have been 8 kword and the X17 would refer to 16 bit word length plus 1 bit parity.

Similar memory boards used by DEC were around $20k.

In the HP 2116 series the B model contains up to two 8 KWord modules. The C model contains up to four 8 KWord modules,


Thanks, Mike! I was hoping someone would fill in the blanks and you did!

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