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Details about  UNIVAC 1050 4k CORE MEMORY STACK 7 PLANES magnetic ferrite model 9150-10

UNIVAC 1050 4k CORE MEMORY STACK 7 PLANES magnetic ferrite model 9150-10

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Last updated on  Nov 25, 2014 13:04:11 PST  View all revisions



UNIVAC 1050 Core Memory Stack


Presented for Buy-It-Now is a Complete 4k Core Memory stack for the Univac 1050 Processor. The Univac 1050 was a mid range mainframe computer. It used discrete transistors to make up the logics. Core memory was it's only internal memory. This CPU was a 6 bit octal satellite computer for the Univac III, from the mid 1960's. The first three images presented are of the item for sale, the remaining images are from previous listings. Please click on the thumbnails to enlarge the images.

I was a Senior Systems Engineer for Univac in Philadelpia Pa. for many years beginning in 1968 to the 80's. I saved this core stack after a swap out for an intermittant problem. We later realized the problem was not in the memory. The problem wound up being in the backboard wiring. Anyway, I saved this stack all these years and now haved decided to sell this to a new home where, hopefully, it'll be appreciated. This item is believed to be a working unit, subject to age and having the correct Univac 1050 CPU to run it in. Note that the retainer at the upper center is missing. I can't remember that we locked these in while the system was operating. This is the last stack I own, one was previously sold.

The Univac 1050 had up to 8 seven bit core memory stacks, each containing 4092 locations which gave the system a maximum of 32k of memory. One unit came standard with the processor purchase and the other 7 were features available for purchase at $10,000 per 4k stack. I sold one of the memory stacks for auction in a previous eBay listing. The computer was released in, I believe, 1965. and the drawings are dated 1962 thru 1965.

This stack includes on both sides the transpacs ( or Transformer Packs ) used in the addressing, as shown in image one and two. The image at the bottom left shows those tanspacs in the logic manual. The image to the right, and the one above it, is looking into what would be the side presented to the opposite side of the "Mother Board" which in those days had a slightly different meaning than today. That view shows the edges of the seven planes that make up this stack. Also shown is the wiring between the planes and the 18 pin connectors that make the connections to the motherboard.

The motherboard had rows and rows of connectors which on the reverse side were connected together with 24 gauge wire. That wire was wirewrapped to the pins with a battery powered wirewrap gun. there was also a manual hand tool to accomplish that task. Each pin could take up to 3 wraps. Each wrap was referred to as a level. Part of the documentation of each system in the field was a set of "Socket Edit" manuals. These manuals spelled out the wiring on the back board or mother board. I can only remember doing any wiring on the 1050 once. On Univac's 1100 systems we did FCO's constantly. The factory machine could only wrap single wires. Univac wanted twisted pair (30 gauge, on these later machines) in the data path which we did by hand in the field on the customers site.

To the right is an image showing a stack I previously sold sitting on the engineering drawing, a part of a separate listing, showing the layout of the 8 memory stacks. This processor used 6 bit octal memory locations which allowed for up to only 64 different characters to be represented. Thus lower case characters didn't exist. The computer used 5 adjacent memory locations to make up a 30 bit instruction word. The computer did arithmetics in decimal or in binary. The Univac 1050 was designed as a satelite to the much larger Univac 3 and many of those that I knew were in IT departments that owned both systems.

I tried to present pictures capable of presenting the condition of the item so that you can make your own decision as to whether this is suitable for your collection. The logic manual is NOT included in this auction. The Logic Manual, is for sale in another (SOLD) eBay listing. This listing is for one 4k Core memory stack as pictured in the first three pictures

Buy-It-Now only $399.95.

Here's a link to a manual on the memory sold here.

Also; the computer history museum has an article with picture of a somewhat similar usage of this same memory stack. It looks like it's on an 18" rack mount frame. I was trained on this memory/computer by Univac in 1968, but don't recognize the memory on the rack as shown there. Perhaps that was a preproduction prototype or possibly a military usage of the same memory. What I remember was what's shown in the image of the core stack sitting on the locator page from the logic manual.

Univac did most of the military work in those days; in fact IBM sued to get some military contracts. If this was a military usage then I might have spent all those years with them and never heard of that computer. Univac had an "FSD division" (Federal Systems Division) and a commercial group. I worked in the commercial group. I had heard of some military computers like the LARC which became the commercial Univac III and the AN/YUK 7 but never saw either. Several years ago I did acquire a lot of memory cards from the AN/YUK7 which I sold here on eBay.

For international shipping we must insist on insuring all packages. All international orders will be shipped by United States Post Office Priority Mail International. That shipping service includes free insurance for at least $68 and increases based on weight. No other nsurance is available. We will give the postal clerk the same value for insurance, and for customs declarations.

We will cancel bids for any bidder with negative feedback or with multiple recent negative feedbacks. We reserve the right to cancel bids from those with private feedback.
The pictures in this listing and the page design are copyrighted by John Duda, 2007, 2011. We will bill for any unauthorized use. In addition we will notify appropriate authorities of the fraudulent use of our images to misportray your item for sale on this site.

The following image is for illustrative purposes only and bears no resemblence to the item being auctioned here. The illustration is from a Univac training manual on the Univac 7013 memory, a much larger much faster memory. Click to enlarge.


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