On 2017-Dec-01, at 7:12 AM, Tony Aiuto via cctalk wrote:
> https://www.ebay.com/itm/263005049078
>
> EBay listing for a "Soviet Magnetic Ferrite Core Memory Board". It looks
> like 20 something gigantic cores and a lot of diodes. I am guessing it is
> some kind of ROM, but it doesn't look like a rope memory. And maybe the
> cores are not cores at all, but some sort of inductor. I've not seen this
> before.
That's very funny.
It looks to be a core rope memory that hasn't been programmed.
Other organisations might be possible, but it looks like a pulse-transformer
type of core-rope,
where the cores are just for ordinary induction, not switching/memory cores.
- the matrix of black what-look-to-be diodes would be data-wire
isolation diodes
- the little brown 'stools' are wire routing posts
- you can see the mulit-turn sense windings (bluish) already present on
the cores
- above the cores are the sense amplifiers or 1st stage thereof
- there is one wire through all the cores, perhaps a test wire for core
and sense amp response
Each data-wire would start at one of the solder pins in the pin matrix on the
left, weave through the cores to encode the data,
turn back 180, then 90 degrees around one of the stools to drop down and
terminate at the solder pin by an isolation diode.
There would be another board for decoding the address to 1-of-x and 1-of-y.
I didn't count precisely but it looks like it would be 256 words of 20 bits.
That might be a date code of 6847 on a cap (or is it 6B47?), so perhaps earlier
than the listing-stated 1981.
Actually, it kind of hints at it in the description: "With out Firmware ROM
wire (empty slots)"
