Hi
All I can say is that those were the words from the
actual engineers that were working on the problem.
Yes, I do believe the disk had coatings but they
were dry lub ( like Teflon ) and none flowing.
Anything that would flow would quickly destroy the disk.
Any lump on the surface would cause the head to bounce.
Anything that flowed slowly would cause a lump.
Since this doesn't happen, it couldn't be. A smoke
particle is a lump. Dust is usually so large that
the head knocks it out of the way.
Still, they said they solved the problem by making
the surface a little less smooth.
If someone opened a disk and saw lube on the surface,
that disk had a failed bearing seal.
Dwight
>From: "Brad Parker" <brad(a)heeltoe.com>
>
>
>"Joe R." wrote:
>...
>>slide (or rotate) just as easily. I've looked at a couple of drive platters
>>that had sticktion problems and there definitely seems to be wax or
>>something holding the heads to the platters.
>
>I think almost all 3 1/2" drive media has some sort of coating on it.
>What it is varies over time and mfg. I remember that most of it had
>'lubrication like' properties - it's been a long time however and I may
>be slightly off.
>
>I seem to recall the magnetic coating was sputtered on and then another
>coating was put on top. As I remember sometimes the top coating would
>pool around the heads after they landed.
>
>but it's all a dim memory and my memories are probably very dated these
>days since the density has gone up by factor of 1000.
>
>I do remember walking through Tony Lapine's labs and watching watching
>drives running inside laminar flow hoods :-) head balistics where the
>order of the day and made for some interesting firmware.
>
>-brad
>
I have 2 sets of BA23 "skins" (the outer plastic covers) available.
One is complete and undamaged (except for the property marking
described below) - has both side panels, front cover, back cover, and
the base "foot".
The other has everything except the back cover, and the "foot" on this
one has a chunk missing from the middle of one edge, maybe about 4"
long.
Both of them have the name of the organisation they came from marked
on the front panel (under the opening for the drives) using the
"SELECTAMARK" system (blue dots which spell out letters in a
dot-matrix-style font). This can be removed with glasspaper, or if you
don't care you can of course just leave it. I suppose this only really
matters if you want the covers for display/museum purposes.
Best offer (to me by private mail) by the end of 21 days takes them.
Your offer can be from "nothing" upwards - I don't mind if these go
for free, but if they're worth more then obviously I wouldn't mind a
few drinking vouchers ;)
You must pay shipping or collect in all cases.
Ed.
> Anybody have a stupid DOS trick for importing binary files
> over a com: port?
MS DOS came with a program to do that. I dont' recall the exact name, but
it was something about a server (check the DOS directory it will probably
spring out at you). You had to setup one side as a server and one as a
client. I don't recall if you had to do it at boot time or not (I had
boot disks setup for it, so I always did it at boot, but that might have
just been the way I set it up).
I used to use it over parallel, but I'm pretty sure it worked over serial
as well (I think I did parallel simply because it was faster).
If you can't find it, let me know and I'll dig up the name.
-chris
<http://www.mythtech.net>
win2K and on will not allow any hardware direct access to hardware. In the DOS days, programs "talked" directly to display cards to bypass BIOS or expected to load their own memory manager (that is the Phar Lap error you are receiving). There are a lot of console programs that will work just fine on XP as long as they access normal BIOS and DOS system calls. AutoCAD is not in that category...
best regards, Steve Thatcher
-----Original Message-----
From: Computer Collector Newsletter <news(a)computercollector.com>
Sent: Jan 3, 2005 11:58 PM
To: cctalk(a)classiccmp.org
Subject: Slightly OT: DOS programs in Win XP
A while ago I asked if anyone on the list could help me get AutoCAD 12 for DOS.
Several people came through and I now have a copy. Thanks, everyone!
As expected though, it doesn't work and play nicely with Windows XP. I was
hoping that just running it through a command prompt window and giving that
giving the Win 95 compatibility attribute to the acad.exe file would make it
work. It didn't and I got a strange error message:
"Phar Lap err 74: Can't use -REALBREAK under this version of DPMI"
So I Google that and found a few threads like this one:
http://discussion.autodesk.com/thread.jspa?threadID=314
Apparently it's just not possible to run Acad 12 in 'real' DOS in XP. I
already knew XP's prompt is nothing close to real DOS, but I was hoping to find
a way to trick the program, or a way to emulate DOS perhaps. Anyone have a
clever solution to this? (I do have a suitable second PC to install real DOS
on, but I'd rather not have to dedicate a whole system just to use one program.)
Like it says, 7 TK50 media, free to good home. All but one have
handwritten labels. They all have cases.
One has a dot-matrix printed label which says:
"AQ-GL5AJ-DN MB26947
MVII DIAG CUST TK50
COPYRIGHT 1987
DIGITAL EQUIPMENT CORPORATION"
so, a MicroVAX 2 diagnostics tape.
Free to whoever wants them, you pay shipping. Please speak up (by
private mail) within 21 days if you want them.
Ed.
If anyone is interested in a nice enclosed 19" rack (5.5 feet tall with
a door, etc. I think it's on casters) it's free for the asking in the
SF Bay Area. Just email me if you have an interest and I'll put you in
touch with the guy that has it.
Erik Klein
www.vintage-computer.comwww.vintage-computer.com/vcforum
The Vintage Computer Forum
It is worth something to me, but at the moment my budget is rather tight. I
didn't mean to 'whine' about it, I was just excited to see such a complete
piece for sale, and was surprised when you bought it. I didn't mean for you
to buy something you didn't want.
I'd say the complete documentation (the stuff in the binder) is worth around
$60 to me, but I don't have any extra money to spend right now.
In about a month I should have enough. I'll e-mail you then.
Jonathan Gevaryahu
jgevaryahu_(a)t_hotmail.com
lord_nightmare_(a)t_users.sf.net
(replace _@t_ with @)
>>>>I hope to see the whole thing scanned (and I want to see the scans too).
>>>And this information is worth how much to you?
>>I was hoping to get scans of the *ENTIRE* Votrax PSS manual
--
>Perhaps you are not a native English speaker.
>I just spent over $200 for something I was not particularly interstested
>in because you were whining on this mailing list about wanting the
>documentation.
>I am not going to put this information up on bitsavers for free. If you
>feel
>this is worth something to you, put up or shut up.
"Joe R." wrote:
...
>slide (or rotate) just as easily. I've looked at a couple of drive platters
>that had sticktion problems and there definitely seems to be wax or
>something holding the heads to the platters.
I think almost all 3 1/2" drive media has some sort of coating on it.
What it is varies over time and mfg. I remember that most of it had
'lubrication like' properties - it's been a long time however and I may
be slightly off.
I seem to recall the magnetic coating was sputtered on and then another
coating was put on top. As I remember sometimes the top coating would
pool around the heads after they landed.
but it's all a dim memory and my memories are probably very dated these
days since the density has gone up by factor of 1000.
I do remember walking through Tony Lapine's labs and watching watching
drives running inside laminar flow hoods :-) head balistics where the
order of the day and made for some interesting firmware.
-brad
