On 11/27/05, Alexey Toptygin <alexeyt at freeshell.org> wrote:
> I'm going to be in southern England for 2 weeks in mid-december, and I
> was wonding if listmembers could recommend any classic computing sights
> I should see while there. Ideas?
Hi Alexey
I would be delighted to show you around the Museum of Computing, we are
based in Swindon, Wiltshire.
Simon Webb
Curator, Museum of Computing
www.museum-of-computing.org.uk
Tel: 07939 582544
>
>Subject: Re: Pinout for SED9421
> From: "Dwight K. Elvey" <dwight.elvey at amd.com>
> Date: Mon, 28 Nov 2005 10:46:28 -0800 (PST)
> To: cctalk at classiccmp.org
>
>>From: "Allison" <ajp166 at bellatlantic.net>
>
>>> From: woodelf <bfranchuk at jetnet.ab.ca>
>---snip---
>>
>>>Did anybody ever use a serial chip and a data separater
>>>rather than a floppy disk controler?
>>
>>Yes, many. usually its a sync chip.
>>
>>Allison
>
>Hi
> Besides the HeathKit hard sectored controller board,
>used on both the H8 and the H89, Polymorphics also
>used a serial chip to do data. In both of these
>cases, as you state, they used synchronous serial
>chips and not async.
Err, Yes that's what I did say. Sync chips were the norm
for brewed designs there were not OSI or done with TTL.
Often they were used because WD could not supply or was
not viewed as the desireable item due to lack of second
source (at least early on). Some did it to have a
propritory format.
Allison
>
>Subject: Re: Pinout for SED9421
> From: "Chuck Guzis" <cclist at sydex.com>
> Date: Fri, 25 Nov 2005 10:36:33 -0800
> To: cctalk at classiccmp.org
>
>On 11/25/2005 at 9:59 AM Allison wrote:
>
>>The all time worst was the 1771 internal data sep. Tandy initally did
>that to save parts. Really bad.
>
>I remember once asking our FDC design guy (he cut his teeth at Sperry ISS)
>about the 1771 on-chip DS. He just laughed and gave a thumbs-down. He
>built his board around the 1781, using GCR and a bit rate of about 380 KHz
>on DS media. The drive electronics needed the low-pass filter tweaked a
>bit to work, but he managed to get about a megabyte on a 5.25" DS floppy.
>Not too shabby for the time (1979).
Tandys EI design got me a few trips to FtWorth to massage their heads
with a bat for what they did.
Yes, 1meg was way above the usual 190k-380k common for for DDDS drives.
The highest I got to with MFM was 800k (80tr 2sided).
>Drives back then tended to have more problems than the controllers did.
>
>In particular, we gave up on Micropolis because of their stubborn
>insistence on using a leadscrew positioner, long after almost everyone else
>went to the faster taut-band. I still have a 96 tpi Micropolis drive that
>employs buffered seek (goes not ready while seeking). It also mounts the
>drive electronics board and the positioner on the movable part of the disk
>clamping assembly. Only the drive motor and tach circuit is mounted on the
>stationary drive frame.
The disk that Shugart used while innovative was really bad for repeatability
of position and slooowwww.
Allison
I'm going to be in southern England for 2 weeks in mid-december, and I was
wonding if listmembers could recommend any classic computing sights I
should see while there. Ideas?
Alexey
I have a box of 10 Memorex "FD VI" Vydec-compatible
8" floppy disks. These are single-sided, double-density
disks with hard-sectored index holes around the periphery
of the disk (on the outside, not near the center hole).
They are labelled as compatible with the Memorex 651 drive.
Note that these are not the more common 32-sector format,
or the even more common soft-sectored variety. As far as
I know, these are useful only for Vydec word processors,
a very early WYSIWYG WP system.
The disks appear to be unused, but are slightly warped due
to improper storage. I suspect they are usable, however.
They are available for the cost of postage to a collector
with a compatible drive, otherwise I will put them up on
eBay, or keep them as "bait" to lure a Vydec into my collection. ;)
--Bill
I have a friend with a machine refered to in Kevin Stumpf's book on
collecting computers.
He owns the Univac III mentioned in a book he published.
Does anyone have a copy of the book, or a contact for Me Stumpf? He
would like
to get the information about the system, which was in the book
Many thanks
Jim Stephens
reply to jws - at - world.std.com, unless info is of interest to list,
please. Thanks
I have a couple of X-terminals that I don't have time to work on and that are therefore looking for a new home.
The NCD19 would probably just work with the right download image. The NCD16 has a problem, which seems to be related to the memory. It does have a good CRT though (the square 16" 1024x1024 mono) and has server PROMs. Might be a good candidate for parting out. The IBM is a bit newer (and therefore a bit off-topic, sorry) and is an NCD OEM product. It's actually a network computer that supposedly does X, Windows Terminal Server, and some Java stuff.
NCD19
June 1991
No keyboard or mouse
Ethernet AUI/Thinwire
Boot PROM V2.2.1
8MB RAM
Cosmetic appearance fair
NCD16
January 1991
No keyboard or mouse
Ethernet AUI/Thinwire
XServer PROM V2.3.0
1.5MB RAM
Cosmetic appearance good
Fails self-test, possibly memory
IBM 8361-110
~1998
No keyboard or mouse
Power-supply
Ethernet 10BASE-T
32MB RAM
Boot Monitor V3.0.7.2
Cosmetic appearance fair
I won't ship, but I can meet anywhere in the San Francisco Bay Area. I am not really asking for money for them, but would consider a trade if you have something I am interested in. Please respond directly in email.
Alex.
I've got an Atasi 1224 cylinder 16 head MFM drive that I want to use with a
WD1000 disk controller. It will be the only drive attached to the
controller.
Pin 2 of the control connector on the WD1000 is RWC/, whereas the same pin
on the Atasi is HS8/. So, I'll have to isolate that connector, but even
so, since the WD can only address 8 heads, I'm stuck with around 70MB of
storage out of a much larger drive.
Has anyone in the same situation simply tried driving HS8/ off of DSEL2/
(pin 28) and jumpering DSEL1/ permanently TRUE? This should give me 2
drives of 1024 cylinders / 8 heads each.
Am I thinking straight here?
Cheers,
Chuck
anyplace that has a Research Machines Nimbus puter.
None to be found on this side of the pond :(
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