Message: 5
Date: Mon, 24 Dec 2007 16:58:17 +0000
From: ard at p850ug1.demon.co.uk
Subject: Merry Newtonsday!
>Merry Christmas, Newtonsday, Yule, Winter Solstice, or whatever you celebrate
>to all members of this list and their families.
----------------
And also from me, best wishes to all for a warm and happy holiday with
friends and family, and a 2008 filled with successful cc restorations, one-
of-a-kind finds, and/or whatever brings you pleasure and joy.
mike
I was just email chatting with Sellam - here's the "scoop" on Vintage
Marketplace:
"Yep, a planned outage. ?We're moving everything over to a new server
and new software. ?It'll take a while. ?I guess I should've done a
better job of communicating this ;)"
Cheers,
Lyle
--
Lyle Bickley
Bickley Consulting West Inc.
Mountain View, CA
http://bickleywest.com
"Black holes are where God is dividing by zero"
On Dec 24, 2007, at 1:39 AM, Richard wrote:
> Origin2000 and Onyx2 Deskside and Rackmount Installation Instructions
> Document Number 108-0155-002
> 12/96
> pg. 6-36
>
> "Caution: You cannot install CrayLink interconnect cabling on a
> standalone deskside system because of power grounding
> requirements. The power differential between two interconnected
> modules should not exceed 500 millivolts; otherwise severe damage
> can result to boards and other components inside the chassis. The
> power distribution unit (PDU) inside the rack provides a common
> ground source for the modules. In addition, the groundstraps are
> installed on multirack configurations to help provide common
> grounding across the racks as described in Section 6.16"
>
> That seems about as blunt as you can get.
I'm not sure about that- you can CrayLink to Origin 200s together, the
only requirement being the common ground (plug them into sockets with
the same ground, run a thick ground between the chassis, or (as I have)
stack them one on another if they don't have the skins).
If you can do it with an Origin 200, then you can do it with a Origin
2000, since the hardware is very similar. You might need to get
creative with the grounding, though, and make sure it's done well
(perhaps two grounding straps of ~12AWG connected to different
locations). Perhaps SGI did not design the ground point into the O2k
deskside as they did in the O200, but we're a creative bunch here.
>
>Subject: Re: Re : 2N2/256-BSCP
> From: Dave McGuire <mcguire at neurotica.com>
> Date: Mon, 24 Dec 2007 11:08:01 -0500
> To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org>
>
>On Dec 24, 2007, at 3:56 AM, ard at p850ug1.demon.co.uk wrote:
>>>> Given that there's a limit on the number of transistors, I don't
>>>> see what
>>>> advantage using SOT23s would give you.
>>>
>>> It'd be easier to assemble.
>>
>> Only if you don't spend hours looking for the transistors that flew off
>> the end of your tweezers :-).
>
> Oh, SOT23s are easy to deal with. 01005-size components are the ones
>that just disappear without a trace.
>
>> My point is that while SOT23s didn't exist 40 years ago, there is no
>> real
>> reason to prohibit them in a project like this. Limit the number of
>> transistors, sure. Insist on an architecture that could be built 40
>> years
>> ago, sure. But should the use of a storage 'scope to debug the thing be
>> prohibited too, on the grounds that hobbyists 40 yrars ago were lucky
>> to
>> have _any_ 'scope? Do you prohibit writing simulators for the
>> transistorised machine, on the grounds that 40 years ago hobbyists
>> wouldn't have had anything to run them on?
>
> I'd have to agree.
Actually the Accutron watch used a very small tansistor to excite the
tuning fork the package was a three legged item of .095" diameter
and 0.130 long with the 3 leads exiting the end. I've had 4 of them
in my parts collection for over 35 years looking for a small project.
Small existed back then. Keep in mind the Apollo Guidence computer
is over 40 years old and that was 3input nor gates!
Transistor computers were near their end 40 years ago with ICs making
inroads. So comments on predominently transistor computers really
have to point to prior to around 1968ish and thats within a week of
40 years ago. The interesting transistor machines are in the time
frame of TX1 through PDP-8 roughly 1957 to 1967 (someon can fine
tune those days).
Anywho the dividing line is around 1963 and prior for germainium
transistors (grown and diffused junctions types) and after then for
silicon devices with superior characteristics.
Allison
>
> -Dave
>
>--
>Dave McGuire
>Port Charlotte, FL
Merry Christmas, Newtonsday, Yule, Winter Solstice, or whatever you celebrate
to all members of this list and their families.
I wonder if anyone will get any classic computer related presents :-). We can always hope... I'll probably spend tomorrow doing what I've been doing for the last few months. Namely slowly restoring an HP9836 (and HP9826, they're very closely related).
I am currently having problems posting to the list. Mail from my home box bounces (something about the time not being compliant with the approriate RFC). I can post from an internet cafe, but obviously not easily over the holiday period. I know I've changed nothing my end, I guess it's an 'upgrade' somewhere else...
-tony
> > Given that there's a limit on the number of transistors, I don't
> > see what
> > advantage using SOT23s would give you.
>
> It'd be easier to assemble.
Only if you don't spend hours looking for the transistors that flew off
the end of your tweezers :-).
My point is that while SOT23s didn't exist 40 years ago, there is no real
reason to prohibit them in a project like this. Limit the number of
transistors, sure. Insist on an architecture that could be built 40 years
ago, sure. But should the use of a storage 'scope to debug the thing be
prohibited too, on the grounds that hobbyists 40 yrars ago were lucky to
have _any_ 'scope? Do you prohibit writing simulators for the
transistorised machine, on the grounds that 40 years ago hobbyists
wouldn't have had anything to run them on?
-tony
> Yeah, you and me both! I had two of them in 1989 or so, a Model =20
> 21 and a Model (I think) 41. I sold the former and ran the latter =20
> for quite a while. It was a really, really nice machine! ZEUS =20
> (Zilog Enhanced UNIX System) performed well and seemed nicely done =20
> overall.
You're convicning me to get mine out and get it running again....
I have a model 30 (I think). It's built in 4 slices. The bottom 2 are
just RS23 distribution panels, then next slice contains an SMD
winchester and a QIC tape drtive, the top slice contains the cardcage. I
remembr looking at the boards and seeing the Z8001 + suppoert devices,
and Z80s on some of the otehr boards (not too suprising).
-tony
Hi,
I've desoldered some IC's off a board from an NEC workstation and there
are two which I can't find any information on. Does anyone know what
they
are or perhaps have a datasheet?
They are:
D65030C022 (48 pin DIP)
B6103C012 (40 pin DIP)
They could be proprietary custom LSI IC's, I don't know.
Also the CRT controller from the boards is a 64-pin DIP Hitachi HD63484
which will be saved for a neat project. I'm thinking of using a 6809
with
UniFLEX, or even a 68000 with Minix, and perhaps making some sort of GUI
for it... A long way off but I can dream :)
Thanks,
Alexis.
> On Friday 21 December 2007 18:33, Tony Duell wrote:
> > I do have the service manual for this drive. The thing I rememebr is th=
> at
> > you don't fiddle with the mechanics without reading it first, and even
> > then tread carefully. There are all sorts of special tools you may need.
>
> That manual have "double sized" pages? That's what the one I have is lik=
> e, I=20
> guess 11x17 or somesuch.
No, it's normal A4-sih pages. Maybe fold-out schemcatis, but I don't
think so.
>From memory, my manaul doesn't say CDC on it, but it's clearly the same
drive, I have a real CDC drive, and everything I've compared is
identical.
-tony
> No, you still need the anode resistor. That's a
> current limiting resistor. It's purpose is to prevent
Rememebr that most glow discharges have a negative resistance. They will
'run away' if you don't include the limiting reisstor until the current
gets so high that the tube explodes (literally!).
> Remember, you don't need any fancy power IC's or DC-DC
> converters - you can just rectify line voltage (an
> isolation transformer is good if you do this...) and
I would never recoemnd running an experimental circuit straight from the
mains without isolation.
Another useful trick (if your PSU already incorporates a normal mains
transdormer) is to connect a small mains transformer of the same nominal
voltage 'backwards' to the secodnary of the PSU transformer. That is, if
you have a mains-9V trasnformer in the PSU anyway, get a small 9V mains
transformer and connect the 9V winding (originally the secondary) to the
secondary of the pSU transformer. You now have an isolated supply of
about mains voltage, from what was originally the primary of that little
transformer.
-tony
