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 at 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