What are the dimensions and weights of a PDP-11/60 in the late model
cabinet - the one that was used on the DECsystem branded PDP-11/70s?
Google image search for "DECsystem 570".
No drives installed.
--
Will
On Mon, 25 Apr 2011 20:50:53 +0100 (BST),
ard at p850ug1.demon.co.uk (Tony Duell)wrote:
>
> I think you're rpobsbly right, the ST has a pretty standaed disk interface.
>
Connecting a new drive involved no more than jumpering for drive select
0, the disk change jumper was already installed. After plugging in it
Just Worked.
> It's always possibl the alignment of that old drive was a bit off, and
> most of the disks youy have were recorded on a misaligned drive. In wichh
> case I guess you should try to get the drive going again anf fiddle with
> the alignment until it can read the disks. And then copy them to new
> disks recorded on a known-well-aligned drive.
>
I'll get round to seeing about getting it working fairly soon. When it
seems to be doing its thing I shall have to see about aligning it.
> Ouch!. That's horrible. The service manuals I have for 3.5" drives (rather
> better 3.5" drives than this one) say that the slide rails are matched ot
> the head assembly, and you can't replace either separately. The
> tolerances are just too tight. I can't believe holes in sheeet metal are
> anything like accurate enough
>
Nothing in this drive appears to be matched in any way. OTOH the slide
rail is eccentric at the ends and has a slot for a screwdriver, so it is
obviously meant to be adjusted. It is supported on tabs bent up from the
metal chassis, and the head slide is made from the same sheet metal.
There are two wide tabs bent out underneath, with holes punched so that
the metal forms a sort of bush for the slide rail. It looks very cheap I
must say.
How would you suggest I lubricate the slide rail? Light oil or some kind
of light grease?
/Jonas
>>>> I moved everything to ZFS several years ago after looking at the
>>> design.
>>>>
>>>
>>> Unfortunately, Oracle controls it now, and there aren't a whole lot of
>>> good
>>> inexpensive choices for that class of scalable storage.
>>
>> It looks like there are several ports to non-Solaris platforms, at various stages of maturity. - Ian
>besides http://zfsonlinux.org/ ?
Having read up on ZFS I am very impressed with the level of paranoia. Especially its distrust of what has become "industry standard" solutions to data storage reliability. E.g.:
* ZFS can not fully protect the user's data when
* using a hardware RAID controller, as it is not able
* to perform the automatic self-healing unless it
* controls the redundancy of the disks and data.
* ZFS prefers direct, exclusive access to the disks,
* with nothing in between that interferes.
That's the level of paranoia that I want! I was always convinced the RAID controllers are only specified to screw me over. I make the folks with tinfoil hats look like wannabes.
I'm trying to find a 2 sided prototype board that's got a male card edge
on it with .156 finger pitch. Ideally a 2*12 (24 fingers) board would be
nice, but I can cut down anything larger.
Google hasn't been much help. :(
tnx.
g.
--
Proud owner of F-15C 80-0007
http://www.f15sim.com - The only one of its kind.
http://www.simpits.org/geneb - The Me-109F/X Project
ScarletDME - The red hot Data Management Environment
A Multi-Value database for the masses, not the classes.
http://www.scarletdme.org - Get it _today_!
Political correctness is a doctrine, fostered by a delusional, illogical
minority, and rabidly promoted by an unscrupulous mainstream media, which
holds forth the proposition that it is entirely possible to pick up a turd
by the clean end.
Al writes:
> Archiving on rotating rust has become a multi-billion dollar industry in the 21st century.
In fact I distrust filesystems, OS's, data busses, etc., more than I distrust the rotating rust.
And the more expensive or complicated the filesystems, OS's, and data busses become, the less I feel I should trust them.
Many years ago I had a hard drive whose write gate failed "safe". You mean I just verified the cache instead of the media?
I don't think I am putting excessive faith in bunzip2 -v, md5, and sha1, but you could try to convince me otherwise.
Silent corruption of data is my worst fear of all. It's even worse than when Mr. Bemis's glasses break at the end of that Twilight Zone episode - it's more like he opened all the books and found them blank. Finding out the data wasn't there where I expected it, is far more disappointing than knowing it's there but I can't see it.
Tim.
I'm having no luck at all installing LOS.
I've tried Lisa Office 3.0 and 2.0, but they both claim they cannot write
to the disk - I tried two 5M and one 10M ProFile. To my knowledge, none of
these have bad sectors. There's no sign that it's even _trying_ to access
the disk. The activity light on the ProFile flickers during _detection_
and I can hear it seek. But, when I push the button to initialize it
comes back immediately claiming it cannot write. I see no sign any access
has occured at this point.
If I try to repair the disk, it tells me to contact a service specialist
and mentions error 200/662. There's no error 200 listed in the Lisa
repair manual, but 662 is ProFile parity error. It's hard to believe
that, since the drive passes format and certify on an Apple /// and
MacWorksXL on the Lisa has no problem with it.
I even tried removing the serialization on Office System disk 1. No joy.
Something tells me I'm overlooking the obvious, but darned if I know what
I'm doing wrong.
Steve
--
> Or vary the spacing between the electrodes or the depth that they're
> immesed in the brine.
>
> Seriosuly, such things have been used, and while they're better on AC
> than DC (due to electrolytic effects), they can be used as PSU dummy
> loads. But solid resistors (be they commercial wirewound ones,
> lengths of
> resistance wirte taken from old electric heaters, or filament bulbs)
> are
> a lot easier to handle.
>
> -tony
This sounds a bit risky to me. Passing a current through brine would
generate hydrogen and oxygen gas AFAIK, as well as possibly chlorine
gas. It sounds like an explosion waiting to happen, unless you have
adequate ventilation. Not the sort of thing I would want on a workbench.
/Jonas
> > > > The reason is quite simple--tungsten-filament lamps (not that I
> > > > expect anyone to have any carbon-filament ones) have a very
> steep
> > > > resistance-temperature curve (higher "hot" resistance).
> >
> > HP remembered this.
> Indeed they did. In the Mdoel 200 Audio Oscillator for one thing ;-)
>
> I am sure it's mentioned in one of Fred Terman's books too, not
> suprisingly...
>
> -tony
IIRC using a light bulb is a/the classic way of stabilising the
amplitude of an audio oscillator. I have seen it in several designs.
/Jonas
All,
I also have a 90s air cooled mainframe. Sadly I have all the hardware but
no Bus and Tag cabling to go with it. I'd like to fire it up, but without
the ability to cable it that's a remote pipe dream. I warn anyone taking
one of these on to make sure they save the cabling from the copper
scrappers as well. ESCON is still easy enough to get. Bus and tag has so
far eluded me so I believe it must be getting thin on the ground. If
anyone does know of a UK/Western Europe source, please let me know about
it!
Thanks,
Colin Eby
