Anyone know anything about these? I've got an image of a hard disk containing
Torch's System V.2 release, which I'm hoping to be able to read under Linux
(which supports sysv, but makes the point that sysv.2 only works on floppies)
Things that would be really useful to know:
1) Was there a standard partition table format for disks containing System V
filesystems? Possibly every vendor perhaps did their own thing, but maybe
there was a standard defined!
2) How do V.2 filesystems on floppy differ from V.2 filesystems on hard disks.
Having looked at the hard disk image in a hex editor, it seems that (at least
in Torch's case), the first 1024 bytes of the drive contain partition table
info. It's hard to deduce the actual format from the data I have, though.
If I strip off the first 1024 bytes of the image, then try and mount the image
under Linux as a sysv filesystem, it gives it a fair old go. I get "VFS: Found
a SystemV Release 2 FS (block size = 1024)" in the logs, but pulling up a
directory listing of the root gives me a few sanely-named files (no
directories), a few files with garbage names, and the following in the logs
for the mounted filesystem:
"Bad inode number on dev loop0: 23130 is out of range"
One of several things looks to be happening:
1) The filesystem/disk image is hosed anyway (probably not, but can't rule it
out right now).
2) The Linux sysv driver - just as the docs say - doesn't work on V.2
filesystems from hard disks, because they differ somehow from floppies.
3) Torch's idea of a sysv filesystem isn't quite the same as everyone else's.
(unlikely, but not impossible)
4) My guess about needing to rip out the first 1024 bytes from the image is
incorrect. (user error :-)
Fingers crossed it's (2), but I'd really like to rule out (4) at the moment.
Assuming it is (2), I'd like to modify the Linux sysv driver so that it *does*
working with hard disk images containing V.2 filesystems, so maybe someone out
there has some spec info...
cheers!
Jules
Hi,
The discussion re: SBC6120 got me thinking (something
I try hard to do only on special occasions! :> )
It's disturbing that it seems so hard for the OP
to scrape up enough interest to justify parts for
another build.
Which brings me to my question(s)...
*Why* aren't people interested in this sort of thing?
- lack of interest (i.e. PDP8? what's *that*??)
- lack of collector appeal ("Ah, but it's not a REAL '8!")
- lack of space ("Hand me a shovel; I'm digging a sub-basement")
- lack of CASH (<frown>)
- lack of skills ("Now, *which* end of the iron do I hold??")
- lack of time ("Honey, little Bobby set himself on fire, again.
Can you please put it out?")
I obviously have a good idea what the reasons COULD be.
But, I'm curious as to what they REALLY are!
In the interests of candor, maybe replies off-list are better?
And, don't interpret this as JUST pertaining to that
particular product/project. I'm curious as to how receptive
(resistant!) people are to *any* sorts of projects like that
(even if they are "already assembled")
Thanks! I hope I didn't step on anyone's toes...
--don
>
>Subject: Re: Tek 555 was Re: Need pointers on Oscilloscopes
> From: ard at p850ug1.demon.co.uk (Tony Duell)
> Date: Thu, 15 Jun 2006 02:03:55 +0100 (BST)
> To: cctalk at classiccmp.org
>
>>
>> On Saturday 10 June 2006 06:03 pm, Tony Duell wrote:
>> > Somewhere I have the issue of Practical Television magazine which gives
>> > construction details for a 1 valve + CRT scope. OK, there are some
>> > semiconductor rectifiiers in the PSU too. The valve is for the timebase,
>> > the Y input goes straight to the CRT plates. But it was useable for the
>> > signals in vavle TVs of the time, and a lot better than nothing.
>>
>> Bet you could do the timebase without a valve, too -- I was looking seriously
>> at a circuit that used a couple of neon bulbs as a triggered devices in a
>> relaxation oscillator some years back...
>
>I think the single valve was a thyratron (gas-filled triode) used much as
>you suggest.
>
>>
>> What did they use for a CRT? I have a 3" one in storage that as I recall
>> wants something like 1000V for an accelerating potential, and a transformer
>> to develop that isn't exactly trivial.
>
>I think it used a normal valve HT transformer (which would give, perhaps,
>700V between the ends of the secondary winding), with a voltage doubler
>circuit.
>
>-tony
Over the years I've bult a few 'scopes for special uses and a 2" crt needs
anywhere from 700-1500 for good focus and brightness (also depends on the
tube). The upside is you only need maybe 2mA so a voltage multiplier is
reasonable. One I built used a quadrupler from a 200V transformer that
also ran the 5 tubes used (mostly 12ax7 and similar). The CRT was 3AP1
(3") that gave ok brightness at 1000V.
At the other end I built a small scope for a HB spectrum analyser using
a D170 (about 1.3"h x 1.5W) square tube that was really decent looking
at 800V. For that I used an old surplus audio transformer as a stepup
using a pair of transistors in the classic self excited power oscillator.
With a voltage multiplier it was easy to get the needed CRT voltage
and because the osc frequency was around 800hz the caps were smaller
too. The H and V amps were transistor and bandwidth tested out around
5mhz with no special effort as it was way more than needed.
It's very doable and with modern HV diodes and transistors it's pretty
straightforward.
Allison
All:
To resurrect an old question just in case someone came across
this since my post two years ago:
> While browsing an early-1980 issue of Compute! magazine, I
> saw a blurb for Rockwell offering copies of the manufacturing
> test program for the AIM-65 computer. The blurb references a
> test manual (#EA74-M800) and a test program listing
> (#EA74-J100). It also indicates that on the manufacturing
> line, two EPROMs with the test program are installed in the
> BASIC ROM slots.
>
> Does anyone have either manual or the ROMs in question?
Thanks.
Rich
Rich Cini
Collector of classic computers
Lead engineer, Altair32 Emulator
Web site: <http://highgate.comm.sfu.ca/~rcini/classiccmp/>
http://highgate.comm.sfu.ca/~rcini/classiccmp/
Web site: http://www.altair32.com/
/***************************************************/
At 1:44 -0500 6/13/06, Ethan (hope it's not too cold down there yet) wrote:
>On 6/13/06, Jim Leonard <trixter at oldskool.org> wrote:
>> I have an HP 4ML next to me that is a decade old and prints(*) as well
>> as the day I bought it.
>
>I bought a 4ML new, back in the day, for about $1100 - still works great.
Our home printer, replacing a Stylewriter that kept blowing
one of its transistors, is a Laserjet 4M+. The printer was free from
Freecycle, a new toner cartridge was around $100 from HP. I suppose
eventually I should hit http://www.printerworks.com/ or similar and
reward the thing for its loyal service with memory, fresh ozone
filters, a service manual, preventive maintenance kit, etc. but it's
hard to justify when it just keeps working and working in its
original configuration.
(OT) I figured out enough of the somewhat obscure front-panel
settings to give it a static IP address which seems not to conflict
with our DSL router-supplied DHCP addresses, so now we can wireless
print to it via our 2-Wire router even though our the router seems to
diss Appletalk. (Contact me Offlist if you want the benefit of my
experience on that.)
I have to add my endorsement.
--
- Mark
Cell Phone: 210-379-4635
office: 210-522-6025
Tony Duell wrote:
Do you also rememebr the PE CHAMP (along with the CHAMPprog and CHAMPUV)?
That was a 4040-based computer system which fitted (not including the
PSU) onto one (large) piece of stripboard. The other 2 units were an
EPROM programmer and UV eraser, of course. I think I have all the
articles for that too...
-tony
---------------------------------------------------------------
Billy:
No, that one doesn't ring a bell. But I was only in England until 1972 when
I was transferred to Canada. Smith's there had the occassional UK magazine
but not every month, and not cheap. Still that way. For example, I really
like MacFormat magazine with the 2 CD's every months. But at Borders, these
cost $15.90, 3x the UK price.
Elektor is worth it, MacFormat not. so I subscribe to Elektor and make
trades for back issues of MacFormat.
Billy
A boxed C64 goes for $208.50 on ebay (Item #8824336692)! Was there
not many sold that had the Canada Olympics logo on the side of
the box? Plus I believe this is an older 64 since it does not
have the rainbow logo in the top left corner.
Cheers,
Bryan
On 14 Jun, 2006, at 05:23, cctech-request at classiccmp.org wrote:
> Maybe it's a trick of the eye, but the old drum printers often
> exhibited a
> lot of vertical misalignment of characters, making for wavy lines
> and very
> annoying reading. Curiously, the horizontal misalignment of
> characters in
> chain, train and band printers didn't seem to matter nearly as much.
>
> I remember that the Univac 1108 hardware manuals were drum printed
> and then
> reproduced and were darned near illegible after a couple of hours of
> miserable reading. By comparison, 1403 output was pristine.
Was it because of poor maintenance? My drum printer has not actually
printed anything
for a decade or more, though as of April it can now feed paper
instead of making burning
smells from the sprag magnet solenoids. IIRC there is some adjustment
to the print
hammers which brings a test print into correct alignment. I've just
looked at some old
printouts and they look OK to read, but when I look for waviness,
there is a little there.
Its a bit like a Trinitron monitor, people used them for years and
then asked why a
horizontal line has suddenly appeared on their screen. They often
refused to admit it
had been there all along and they had just not noticed it.
Roger Holmes
(this is a resend of prior reply with no subject)
Jochen Kunz (jkunz at unixag-kl.fh-kl.de) wrote:
> The small desktop 3000-300 machines use PS/2 RAM. The large desktop and
> tower machines like 3000-500 / -600 use proprietary SIMMs.
I used to have a dec 3000-800, nice machine. Wish I'd kept it when I moved.
IIRC, the proprietary simms were used on a 256 bit wide memory path, so that
series had pretty zippy memory for it's time, much faster than the 3000-300
machines (if you could find the propietary memory). And the bigger machines
used more power.
Found a good listing of the dec 3000 machines here:
http://www.phys.ufl.edu/~prescott/linux/alpha/dec3000-sysinfo.html
Short version:
small low-end machines (used 72pin parity simms) were:
* DEC 3000/300
* DEC 3000/300L
* DEC 3000/300X
* DEC 3000/300LX
high-end machines (used propietary simms) were:
* DEC 3000/400
* DEC 3000/500
* DEC 3000/600
* DEC 3000/700
* DEC 3000/800
* DEC 3000/900
Jeff Davis
