>My expeirience is that if you have a drive with a correctly-aligned
>positioner/head assemly, you can remove it as an assembly, and put it
>back in _the same drive_ and it will still be alighed. But if you move
>positioenrs between drives you have to do a realignment.
In my case unfortunately that would not be the case as the best I can find
are two other units in unknown condition from a completely different set of
drives.
>The alignment procedure is not hard if oyu have the alignment pack. You
>also need a 'scope (but just aout any 'scope will do) and a way of moving
>the heads to a particular cylinder and selecting head 0 or head 1. I had
>no prolems using a PDP11 + the appropriate controller for this, just
>togging values int oteh controller registers from the PDP11's font panel.
>If you use a PDP9/e, I think you have to write a trivial program for this.
I can easily get hold of a scope but a calibration pack is a different
story.
>THe disk packs are different between the PDP8 and PDP11 systems. They're
>hard-sectored (by notches in a metal ring on the disk hub), PDP11 packs
>are 12-sectory, PDP8 packs are 16 sector. The former are _much_ easier to
>find.
I think if I could find the rest of the system I might also find the packs
as well. Since this was a local and very little known recycling job only a
few businesses in town and university staff drop stuff off. I really wish I
knew dropped this off but alas, no records are kept on who drops off what.
My best bet is either the hospital or it came from someplace in the
university. Where exactly I have no idea.
On 11/24/09, Fred Cisin <cisin at xenosoft.com> wrote:
> On Tue, 24 Nov 2009, Kirn Gill wrote:
>> I was thinking recently, and I know that the general threshold for
>> discussion on this list is ten years, but is that enough?
Guideline, not threshold. There are countless exceptions on both sides.
>> As it stands, given the rule of a minimum of ten years, most early
>> Pentium III PeeCees are listworthy for discussion.
Guideline, not threshold.
>> In just two more years time, the world's most popular computer operating
>> system (as of the time of this email's writing) would be perfectly valid
>> to discuss, even as "on-topic". 2001 to 2011 is ten years, isn't it?
>
> NEVER!
> There are better places for THAT discussion.
Indeed.
The results of one of the many recurrent discussions of "The 10 Year
Rule" is that it really comes down to "interesting machines are in,
mainstream machines are out". The list of what falls in and what is
still out, changes from year to year, but a rule of thumb is that
there are plenty of places to go to ask for help fixing your Windows
PC, and this is not the place for it.
At one time, when MS-DOS was still in common use all over the planet,
this was not the place to talk about those sorts of machines. I would
suggest that now, DOS knowledge has become esoteric (the slide
starting with the release of Windows 95, one could argue), and that
discussion of boxes running MS-DOS could be on-topic. I would still
suggest that Windows 98 and newer are quite off-topic and will be for
a large number of years into the future (meaning
greater-than-the-quantity-10). Windows 95 is kinda on the fence to me
since there's a disconnect with Win98-and-later. Practically
speaking, if you are fiddling with Windows 95 at this point, it's
because you want to experience how things were 14 years ago. Windows
98, though, I would argue, is new enough that it's still a "modern"
experience.
If you wanted to discuss the Pentium FDIV bug and which chips were
affected, I'd think that was on-topic. If you wanted to discuss what
Windows drivers are needed for that very same machine, I'd say that's
off-topic. Same hardware, different sides of the line. "Ten Years"
isn't (and hasn't been for a while) the be-all-end-all criterion.
-ethan
Hi folks,
there are some Siemens items in Kiel. Free for pickup. Will go to scrap if nobody wants them.
The first two pictures:
http://pdp8.hachti.de/gallery/endangered_stuff
There's also a big printer (one TON!!) in another room. That unit's future will be the scrapyard as
well if nobody is interested in it.
Best wishes,
Philipp
--
http://www.hachti.de
>Maybe someone with a spare drive that could be dismantled and someone
>who could create the specific hardware to write analogically the pack,
>could create a machine for creating alignment packs?! :o)
>
> It was done before with 5 1/4 disk drives... :oD
Hmm, I was under the impression that the alignment packs had everything
hard-coded as to ensure the alignment went okay.
John.
Hi Everyone. I have no idea what these things are called. They show up on
ebay all the time and look like entire 486 machines on a full-length 16-bit
isa card. I'm assuming these are designed to be plugged into a passive back
plane.
I've always wanted to tinker with a computer of this design, but I haven't
had any exposure to them. Is there anything I should look for or avoid
before trying to buy one of these boards? Thanks.
brian
Hi all,
First post here. Long story short, I recently rescued a friend of mine's
Commodore equipment after he'd suffered a fire in his apartment. None of
it caught on fire but some copped a direct hit from a fire hose and was
sitting there for 4 days while I went through the bureaucracy of gaining
access to the place (he's in hospital at the moment but will recover, for
the record).
While this gear isn't particularly uncommon (although the Amiga stuff
might be quite expensive to replace), I'd like to rescue it for him even
if it's just for morale purposes.
Anyway, rusty RF shields have leaked rusty water all over the PCBs and I
really don't know how to deal with it. So far, I've used dry cotton
buds/q-tips to clean off anything visible, but I'd like to know what
people recommend for cleaning the boards properly.
I was thinking isopropyl alcohol - I've previously used it for leaked
caps, but I'm all out right now. Is methylated spirits a bad
substitution?
Speaking of leaked caps, it looks like the water has caused a lot of caps
to leak as well - I've never seen leaking caps in the act, it's always
been dry "after the event" type damage. If there's anything worth noting
about this, that'd be great to know too.
Thanks for any advice!
Cheers,
Dave.
>If the head/voice coil assemblies have been removed you'll have to go
>through the entire alignment procedure which requires a special
>alignment pack. You'll also want to make sure that all of the dreaded
>"DEC foam" has been removed and replaced or you're heads and packs
>won't last long. You'll also want to look at the filters and make
>sure they're in good shape and replace them (if you can find them).
>However, bad filters will also kill the heads and packs.
>
>If the head/voice coil assemblies have been removed how do you know
>that the drives are working?
I noticed that foam almost immediately, I cleaned up the majority but I'll
probably go over the thing with a scraper and the air compressor. I got the
same nasty foam in my SGI Crimson.
Well at the very least the drive powers up with no nasty smells or noises or
the fault lamp and I can get the spindle motor to spin up
>They're one of the standard DEC lamps. I don't recall off the top of
>my head what the equivalent lamp # is but they (or a reasonable
>facsimile) are readily available.
Awesome, that might be a bit better as well.
>For an omnibus PDP-8 you need an RK-8E controller that goes in the
>omnibus chassis. The "hard" part is finding the cable that goes from
>the RK-8E and the drive. For a PDP-11 (unibus) you need an RK-11D
>controller. It is actually a 4 board set in it's own backplane that
>goes in the CPU chassis. There is also an RK-11C for unibus but that
>controller is of the "old style" that has 40 or so flip chips in a
>rack width backplane and is mounted outside of the CPU chassis in a
>rack (requires a separate power supply) that connects to the CPU with
>unibus cables.
Hmm, that might be a bit of a problem as I never see spare flip chips or
anything unless they are on ebay for funky prices.
>If you're not looking for a "blinken" lights machine, you're best bet
>would probably be an 11/34 system. I have several that are "spares"
>but right now I'm swamped and haven't been able to spend any time on
>classic computer stuff.
>
>TTFN - Guy
Well right now I'll go for pretty much anything. I guess a 34 or similar is
a good starter system and on some distant day I'll switch to say an 8/e.
John
Hi guys,
Before I start writing a data decoder of my own (for the disc
analyser), I'd rather like to at least make sure the hardware is
spitting out sane data. Does anyone know of a tool along the lines of
cw2dmk that can accept timing-data input from a file instead of using
(e.g.) a Catweasel?
I was going to do the hardware tests with cw2dmk, but I don't fancy
my chances at figuring out how the ~2500 lines of code fits together,
and how to patch in read-from-file support...
(Apologies if cw2dmk actually /can/ do this; the manpage explains how
to change the output file name, Catweasel port and such, but not how to
make cw2dmk read transition timing data from a file)
Thanks,
--
Phil.
classiccmp at philpem.me.uk
http://www.philpem.me.uk/
Hi at all,
it past much time during i collected all useful info on this my old board
putting all on my website http://elazzerini.interfree.it
<http://elazzerini.interfree.it/>
I hope to can make my board alive soon. A friend given to me all its 32 x
4116 DRAM chips after to have checked all of them.
I buyed on ebay the SWP Double side double density adapter
http://elazzerini.interfree.it/Foto560.jpg and i here to ask: is there
anyone who could indicate where or how to gain the firmware for the bigboard
1 to can make this adapter working or just to gain its 27 original manual?
Thanks for any kind of useful suggestion and please sorry for my not perfect
English.
Enrico Lazzerini - Pisa - Italy
