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Any place in the world that might still make Core Memory ? ....I know it's a stretch

Ragooman

Experienced Member
Joined
Apr 27, 2005
Messages
162
Location
Pittsburgh,PA
Think there's any place left in the World that might still make Core Memory ?

I know it's a stretch

I've read that the ordinary Ferrite Cores that being sold aren't good enough - as they are the 'Soft' Ferrite Cores. You actually need 'Hard' Ferrite Cores which retain the magnetism, and having a sharper BH curve, as in the original Core Memory modules.

I hate to strip the Cores from an old memory module - even if it were something that had no chance of reviving. Plus, I hate to have to sew 'n thread a Core memory :)

I recently found a reference to a seller in Bulgaria on eB@y which does sell 'Hard' Ferrite Cores by the hundreds.


Dan
 

barythrin

Veteran Member
Joined
Oct 5, 2005
Messages
6,256
Location
Texas
Might be an interesting nitch market for someone who likes sewing. I'm not aware of anyone personally but there is a thread of a few folks here who were bored enough to start making their own cores by hand. Of course most were small proof of concept sized projects and it might be difficult to create the interface for whatever you're trying to use it with.
 

Ragooman

Experienced Member
Joined
Apr 27, 2005
Messages
162
Location
Pittsburgh,PA
I've been scavenging any recent info from several webpages on any work done recently - besides looking at original documentation. It's nice to see some other people still taking an interest in this. I've been contemplating on whether it will be practical to turn this into a workshop for the next event. Basically a generic storage device using Core memory that could attach to your vintage computer using a generic interface such a serial port. And using some additional software drivers to command the data to be redirected over the serial port to the Core memory to save any programs, etc. I'm not sure if enough people can be found with enough patience to thread cores - no matter how much of a die-hard you might be.
 

Ragooman

Experienced Member
Joined
Apr 27, 2005
Messages
162
Location
Pittsburgh,PA
I'm looking into getting some of the Ferrite Cores from that seller in Bulgaria. That reference I mentioned is from another Core Memory project here https://sites.google.com/site/wayneholder/one-bit-ferrite-core-memory
http://www.ebay.com/itm/1000x-VINTA...752?pt=LH_DefaultDomain_0&hash=item484fa08f08

I was contemplating building a test jig to "automate" the process of building a core memory plane. Basically it would involve a machined plate with pockets holding the ferrite cores and the X,Y channels to slip the magnet wires thru the cores. These plates would sandwich together, holding the cores in place while you slip the wires thru from the sides. The ferrites are only 1mm in dia. It will take some damn good tight tolerance to get this machined, about +/-0.05mm. I'm not sure if this make it extremely expensive to get this farmed out to someplace.
 

woodchips

Experienced Member
Joined
Nov 4, 2012
Messages
422
Location
UK
My goodness, inflation with ferrite cores! I bought a box of 45,000 around Christmas costing about £50 or so. Another of those projects to be done. Then there were two sizes of core available, small and very small. I think the larger was 1.2mm od and the smaller 0.8mm od, and the difference is really significant. I as trying the thin 'Road Runner' solderable enamel wire available in the UK, this fitted happily in the larger core, but not the smaller.

Do a search on this forum, there was several pages of comments on core stores and making them.

I have just bought a core store off ebay in the UK, be interesting to see what it is when it arrives.
 
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