I'd really like to have something like one of the old
mainframe/minicomputer control panels for my PC, but I'm just not sure
how to implement it. Anybody here tried something like that? Ideally,
you could power it on, see registers, toggle stuff into memory, have
lights for interrupts, that kind of thing. Yeah, I know, as soon as I
bring up an operating system, the ability to toggle things into memory
would be rather dangerous, but I just can't resist the charm of the
idea :)
So... doable? Impossible? Improbable?
John
--
Ph'nglui mglw'nafh Cthulhu R'lyeh wgah'nagl fhtagn
Yo umay rememebr my recent posting aasking for information on the damper
assembly on the head carriage of a full-height 5.25" MPI floppy drive.
I've done a little more work on it.
Firstly, it appears the damper ron was glued ot the head carriage. Since
this makes it very hard to work on (fitting the tension abnd is difficult
at the best of times!), I cleaned out the holes, and drilled (1.6mm) and
tapped (M2) an extra hole in each of the plasic rackets that hold this
rod, 0.2" away from the existikng hole. I then screwed little rass plates
in place to keep the rod in.
Secondly, I've assembled (but not aligned) the positioned. Fittlng the
tensio band ais a pain, I now think that little O-ring I found on one of
the pins is an assembly aid to keep the tension band on that pin when
you're trying to fit the other end in place. I will order some more
O-rings (the pins are 1.5mm diameter, BTW) and see how I get on.
Thirdly, I've had the positioner running on a disk exerciser. WIth a 6ms
step rate (which seems about right), it sounds _much_ rougher with the
damer wheight not fitted. Even without any grease (other than that I've
not managed to clean out) on the assembly, fitting the weight makes it a
lot smoother.
Fourthly, I _still_ can't see how the grease is kept in place, and why it
doesn't just leak all over everthing.
-tony
For those who've not seen it yet...
In this month's Elektor magazine (or at least in the UK edition of it),
there's a 2-page 'Retrotronics' article giving a design for a Dekatron
counter driving a nixie tube with 6J6 (ECC91) triodes as buffers.
-tony
I am not a selectric guru, but I have one and I think that the most likely
cause is that the lubricant has dried out, isn't lubricating and in fact is
acting like glue or adhesive. The "right" way to fix this is to have the
whole mechanism immersed in a bath of solvent (quite a few things have to be
disassembled and removed before this is done) to clean off the old
lubricant, and then relubricated afterwards. This used to be common, but
there are not many places now that still do it and it's expensive (probably
a couple hundred dollars). I have a full IBM service manual for the
Selectric II, which is virtually identical to your machine, but I only have
it in hard copy, not PDF, and it's bound. Perhaps there is a PDF copy of
this manual on the 'net somewhere. A guy who did the immersion cleaning
used to advertise his service on E-Bay, you might to a search there, or a
google search.
Barry Watzman
Watzman at neo.rr.com
PS - Actually I found the contact information for someone who was still
doing this at least in 2006. His name is Rich Wiley, he is at 800-552-8592
and his E-Bay ID was coyote0153.
YouTube doesn't stream. It slowly downloads the flash video files to
the temporary internet files folder where it's usually named "FlaXX.tmp".
The XX is usually a hex number depending on how many tmp files you
have in there. The file is also (99% of the time) deleted the second you
close the page it is linked to.
The good thing is that you can watch the video before it's fully
downloaded. A very good thing if you are on dial-up :)
Does anyone have a list of retro video's on YouTube? I know most can be
found by searching for the appropriate machine name, but not everyone
has decent tags with there videos :(
Regards,
Andrew B
aliensrcooluk at yahoo.co.uk
woodelf <bfranchuk at jetnet.ab.ca> wrote:
Right now I am trying to VIEW the %$@! You-Tube stuff. I hate
streaming
stuf on dial up. I don't think I will ever get more than the 1st few
minutes
of the UNIVAC stuff. Nothing like comparing almost 60 years of
computing
development.
> Cheers,
> Chuck
>
The same CPU and FPU are sued on the KA630cpu (uVAXII) and in early
microvax3100s so any of them should compare.
Is it possible that someone has overclocked the that uV2000???
FYI: gate leakage would kill the chips not make it run hot. The
usual reasons for hot running are:
Over voltage!
Overclock
Undercool
Excessive bus loads (capacitive or resistive)
Since the machine is a closed system for the most part the first is
most likely and the others are least likely.
I may add that over 60C is way too hot at the heatsink and the die
due to thermal resistance will be hotter.
I'm trying to pull down one of my uV2ks and fire it up.
Allison
>
>Subject: Re: VAXstation/MicroVAX 2000 CPU/FPU overheating?
> From: "Dave Dunfield" <dave06a at dunfield.com>
> Date: Fri, 29 Feb 2008 08:18:31 -0500
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>> I assume these CPU and FPU chips are MOS devices. Is it possile that
>> excessive leakage across the gate oxide layer in some transsitors of that
>> chip would cause it to run hot, but still work? I'm pretty sure I've seen
>> chips that seem to work, but get hot and then stop working, althoguh
>> cooling them with freezer spray keeps them running. And these were not
>> chips driving high pwoer laods -- they were things like the clock/timer
>> microcontroller in a VCR.
>
>Yes, I'm wondering if it's something like that, however how likely is it
>that both devices would experience the same fairly-uncommon failure mode
>at the same time?
>
>Perhaps I've been engaging in the persuit of an undomesticated ornithoid...
>
>Is it possible that the devices normally run this hot, and the failure is
>occuring for another reason (possibly a side effect of the heat, as cooling
>them does allow it to keep running).
>
>Allison said "they do run hot" - does anyone know how hot?
>
>I did some further tests last night - I dug out my thermocouple and made
>some actual heat measurements with the system assembled, but with the color
>frame buffer removed - there should be better airflow, and this appears to
>be the case, since the machine did not die after 10 minites of operation.
>
>Ambient temp was measureing about 25 degrees C at the start of the test.
>>From power on, the CPU and FPU rose rapidly (within 3-4 minites) to
>the 70C range, then more slowly rose to temperatures of 76C for the CPU
>and 82C for the FPU after 10 mins. At this temperature they seemed to be
>getting stable - having done nearly 1-1/2 mins without an increase. It's
>possible/likely that they would climb anothe few degrees in extended
>operation.
>
>Once this temperature was reached, I held the system in RESET, and
>observed that the temps dropped back after a few minites to about 64C
>for the CPU and 68C for the FPU.
>
>To my mind, a processor running at 80C is damn hot - most of the embedded
>devices I work with list absolute maximum running temperature as 70C or
>75C - but perhaps the DEC devices are designed to run hotter - I note the
>Intel 486 datasheet lists absolute maximum (under bias) as 110C ...
>
>Anyone on the list with a VS 2000 or uVAX 2000 that can do some temperature
>measurements?
>
>Dave
>
>--
>dave06a (at) Dave Dunfield
>dunfield (dot) Firmware development services & tools: www.dunfield.com
>com Collector of vintage computing equipment:
> http://www.classiccmp.org/dunfield/index.html
On 28 Feb, 2008, at 08:16, cctalk-request at classiccmp.org wrote:
>
> Message: 25
> Date: Wed, 27 Feb 2008 23:38:42 -0800
> From: "Chuck Guzis" <cclist at sydex.com>
> Subject: Re: Speaking of PPT (was: Re: Friden Flexowriter)
> To: "General Discussion: On-Topic and Off-Topic Posts"
> <cctalk at classiccmp.org>
> Message-ID: <47C5F482.14707.21D48412 at cclist.sydex.com>
> Content-Type: text/plain; charset=US-ASCII
>
> On 28 Feb 2008 at 7:49, Jos Dreesen / Marian Capel wrote:
>
>> The latest HP papertape reader I sold on Ebay fetched all of 5
>> Euros......
>
> I know that PPT readers can really zip right along, but what's the
> fastest perforator ever made? Laser-driven, maybe?
Catching up on old messages.
The manuals for my ICT 1301 refer to the standard paper tape punch,
and it ran at 300 characters per second and had a check reading
station to verify every character punched before winding the tape
onto a reel. Unfortunately I don't have one of them but my 1301 does
still have one (of two) of the Elliott tape readers which runs at
1000 characters per second and which have a tape un-roller to prevent
any drag on the reader itself. At 1000cps, the tape comes out almost
horizontal from the reader and a bin has to be positioned correctly
to catch it. Even at full speed, the reader can stop on character
unlike the earlier Elliott tape readers, which was why when I worked
for Marconi-Elliott Avionics, all text tapes were punched with four
null characters after every line termination (ASCII CR-LF or
Flexowriter newline). Binary tapes were expected to be read all in
one go without stopping.
My own Flexowriters have round military style Cannon plugs for I/O
and use 110v signal levels designed for relay logic. A previous owner
of my 1301 has grafted on a large Vero board full of discrete
components, TTL and relays to drive one of the Flexowriters for
output, and an old ICT keypunch keyboard for input as well as a
smaller board to output to a Teletype BRPE (100 cps) paper tape punch.
The non standard online Flexowriter and keyboard are currently
disconnected and I control the 1301 the same way as 99% of 1301s were
controlled via the control panel, which is, I estimate, 4 feet wide
by 2.5 feet high. Most programs are small and I key them in through
the front panel as I can't find anyone to repair my IBM keypunch.
Hi All,
Thanks to some very generous help from a few friends, I have been able to
finally locate a boot disk for the WaveMate Bullet. In addition, I was able
to repair the unit and now it boots and seems to be working at least to some
degree.
Along the way, I gathered up a lot of disk images, documentation, files, and
assorted other items related to the WaveMate Bullet. As this is a rather
unusual vintage computer I am considering storing this cache of stuff online
someplace to help any other prospective WaveMate Bullet owners.
My first reaction is to start another Yahoo! Group but I know a lot of
people here absolutely hate those so I thought I'd poll the list to see if
anyone could suggest a more palatable alternative. My requirements are
simple; just a small amount of file storage, a simple web interface, and a
mailing list.
Thanks!
Andrew Lynch
