Info about a Mullard Core

[Gavin Melville]

Hi Roger,

I was told that was the price of just the core.   The guy who gave it to
me was a little unusual, but told me he tendered for the removal of the
mainframe, and offered money, where all the other tenderers wanted
money.  It was inaccessable, and had a magnetic drum which weighed tons.
The machine must have been large -- he did bring back 1000's of small
boards, which appeared to be just one function per board (and/nor/ff
etc).  I do somewhere have the earth lead for the -6v power supply, and
the lugs off that would fit over 25mm bolts.   Most of the machine went
to a scrap metal dealer in Dunedin.

While I have no idea if it actually came from that machine, it was by
the standards of that time a very large core -- 19200 x 48 bits is
larger than I can find details of -- at least on the net.   The machine
would have been scrapped around 1988 or 1989.

> -----Original Message-----
> From: cctalk-bounces at classiccmp.org 
> [mailto:cctalk-bounces at classiccmp.org] On Behalf Of Roger Holmes
> Sent: Thursday, November 01, 2007 1:38 PM
> To: cctalk at classiccmp.org
> Subject: Re: Info about a Mullard Core
> 
> Hi,
> 
> > From: "Gavin Melville" <gavin.melville at acclipse.co.nz>
> > Subject: Info about a Mullard Core
> 
> > Hi,
> >
> > I have had for many years a large core, and while I don't 
> really want 
> > to part with it, I also see what little pieces of core sell for on 
> > ebay....
> >
> > I was told when given this about 15 years ago that it was from a 
> > Burroughs mainframe which was installed at the Cadburys 
> head office in 
> > New Zealand and that they had paid GBP 20,000 for it in 1960.
> 
> 20,000 for the core or for the mainframe?
> 
> How sure are you about it being Burroughs? Wouldn't they be 
> using U.S. components rather than British?
> 
> I know Cadburys bought an ICT 1300 series machine around 
> 1963/4, and its now in a museum in NZ. It was a 48 bit 
> machine, but I think it had a much smaller store of 1200 or 
> 2000 words and would have cost around 100,000 GBP. I have 
> read there was an option to replace all the 'barn door' core 
> stores with a single store of 4,000 words of 48 bits, though 
> I've never seen one, nor the logic diagrams. I have always 
> wondered whether it used a full binary decode (using 16384 
> words to provide 4000 words of usable memory) of the 14 bits 
> rather than a BCD decode. The 1300s use lots of Mullard components.
> 
> Just a small piece of a jigsaw puzzle, maybe not even the 
> right puzzle!
> 
> Roger Holmes.
> Owner of the last working ICT 1301.
> 
> 
> 
> >   I have
> > been unable to find out if this was correct however.   Does 
> anyone on
> > the list know anything about it ?
> >
> > pictures at http://www.flickr.com/photos/8788341@N05/?saved=1
> >
> > There are 921600 cores in the array, which is made up of 
> 48x48 cores, 
> > 4 to a layer and 100 layers.
> >
> > _________________________________
> >
> > Regards,
> > Gavin Melville
> > Senior Engineer
> > Acclipse Electronic Ltd
> >
> 
>