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MFM controller cards

I need to find at least one MFM HDD/floppy controller card to try to
get into my old system. My billing files and some other programs which
I would like to back up are on on these drives. I think my controller
failed. I could really use another of these drives if anyone has one
also but if not I would be happy just to find a controller board
initially. I'm running two Seagate St251 drives. I've looked just
about everywhere for these things. If anyone has any of this old
stuff lying around they don't need and would like to sell, (or part
with, or whatever), please let me know. I would be very grateful.
Thank you. Lenny Stein, Barlen Electronics.
 
J

James Sweet

Jan 1, 1970
0
I need to find at least one MFM HDD/floppy controller card to try to
get into my old system. My billing files and some other programs which
I would like to back up are on on these drives. I think my controller
failed. I could really use another of these drives if anyone has one
also but if not I would be happy just to find a controller board
initially. I'm running two Seagate St251 drives. I've looked just
about everywhere for these things. If anyone has any of this old
stuff lying around they don't need and would like to sell, (or part
with, or whatever), please let me know. I would be very grateful.
Thank you. Lenny Stein, Barlen Electronics.


I just did an ebay search and came up with more than 30 various MFM
controllers, most are pretty cheap.
 
H

Homer J Simpson

Jan 1, 1970
0
I need to find at least one MFM HDD/floppy controller card to try to
get into my old system.

Ask your local computer recycler to look out for one for you.

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J

JANA

Jan 1, 1970
0
You may be able to find a MFM controller, but it may not work with any of
the mother boards past the 368 or 486 era.

As for the new mother boards, the expansion slots would not be compatible,
and also the BIOS may not see the MFM controller.

What I would do, is get an older working computer that has MFM drive
support, and put everything to floppies to transfer it across. Networking a
very old dos computer to a Windows based computer may not be worth the
effort.

I would be curious to know why you did not have everything backed up on
floppies or something in the first place?

--

JANA
_____


I need to find at least one MFM HDD/floppy controller card to try to
get into my old system. My billing files and some other programs which
I would like to back up are on on these drives. I think my controller
failed. I could really use another of these drives if anyone has one
also but if not I would be happy just to find a controller board
initially. I'm running two Seagate St251 drives. I've looked just
about everywhere for these things. If anyone has any of this old
stuff lying around they don't need and would like to sell, (or part
with, or whatever), please let me know. I would be very grateful.
Thank you. Lenny Stein, Barlen Electronics.
 
R

Rick

Jan 1, 1970
0
I need to find at least one MFM HDD/floppy controller card to try to
get into my old system. My billing files and some other programs which
I would like to back up are on on these drives. I think my controller
failed. I could really use another of these drives if anyone has one
also but if not I would be happy just to find a controller board
initially. I'm running two Seagate St251 drives. I've looked just
about everywhere for these things. If anyone has any of this old
stuff lying around they don't need and would like to sell, (or part
with, or whatever), please let me know. I would be very grateful.
Thank you. Lenny Stein, Barlen Electronics.

Before you buy, why do you think the controller has gone bad? In a
system old enough to use MFM drives there could be a lot of reasons for
a problem. What's the system doing or not doing? Any POST error codes?

Have you tried the obvious first? Pulled the conroller card, cleaned the
card contacts and reseated the drive cables? You may want to clean the
contacts on the drives too - considering they use card edge connectors.

Rick
 
W

William R. Walsh

Jan 1, 1970
0
Hi!
Before you buy, why do you think the controller has gone bad? In a
system old enough to use MFM drives there could be a lot of reasons for
a problem. What's the system doing or not doing? Any POST error codes?

Good points, all of them. Checking to be sure that the system's CMOS battery
is still running would be an excellent idea. After years of sitting it could
be dead or depleted. (Many older motherboards used a rechargeable NiCad
"accordion pack" battery.) If yours has a battery like this, leaving the
system powered on overnight might bring it back up. They do seem to be
pretty robust.
You may want to clean the contacts on the drives too - considering they
use card edge connectors.

Be ***very*** careful if you do this! If you can help it, do *not* remove
those hard drives from the system unit. ST-251 drives have stepper motor
head actuators that are subject to falling out of calibration with the
information stored on the drive platters if the operating temperature range
changes or the drive is removed and reinstalled. There are only two ways out
of this if you get the drives working--either hope that you can find the
right climate/installation "sweet spot" or low-level formatting. Low level
formatting will destroy all data on the drives.

William
 
S

Sam Goldwasser

Jan 1, 1970
0
William R. Walsh said:
Hi!


Good points, all of them. Checking to be sure that the system's CMOS battery
is still running would be an excellent idea. After years of sitting it could
be dead or depleted. (Many older motherboards used a rechargeable NiCad
"accordion pack" battery.) If yours has a battery like this, leaving the
system powered on overnight might bring it back up. They do seem to be
pretty robust.


Be ***very*** careful if you do this! If you can help it, do *not* remove
those hard drives from the system unit. ST-251 drives have stepper motor
head actuators that are subject to falling out of calibration with the
information stored on the drive platters if the operating temperature range
changes or the drive is removed and reinstalled. There are only two ways out
of this if you get the drives working--either hope that you can find the
right climate/installation "sweet spot" or low-level formatting. Low level
formatting will destroy all data on the drives.

Can you cite a reference? In my experience, MFM drives are about the
most robust things on the Planet. :) The tracks are so far apart that
normal temperature changes have no effect. I have some ST-251s (I think
that is the model) sitting at the bottom of a closet. I bet if I could
find a system today to power them up, they would work just as well as
20 years ago (if the grease hasn't congealed).

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
 
K

Ken Weitzel

Jan 1, 1970
0
Sam said:
Can you cite a reference? In my experience, MFM drives are about the
most robust things on the Planet. :) The tracks are so far apart that
normal temperature changes have no effect. I have some ST-251s (I think
that is the model) sitting at the bottom of a closet. I bet if I could
find a system today to power them up, they would work just as well as
20 years ago (if the grease hasn't congealed).

Hi...

Anyone else remember "stiction" ?

Take care.

Ken
 
G

Geoffrey S. Mendelson

Jan 1, 1970
0
Ken said:
Anyone else remember "stiction" ?

Sure. It started out on 40meg Quantum brand 3.5inch SCSI drives. Due to the
quickly changing technology, Quantum got as far as the LPS (Low power) 105 meg
drives before they found out about the problem and replaced the grease.

I've heard of a few 20 meg drives having it, but have never seen one.

Where there other manufacuters?

As far as I know, it never affected MFM/RLL/IDE drives.

That was in the early 1990's. By now, most drives of that age of any
type and manufacturer may be afflicted by it.

Geoff.
 
J

Jeroni Paul

Jan 1, 1970
0
Sam said:
Can you cite a reference? In my experience, MFM drives are about the
most robust things on the Planet. :) The tracks are so far apart that
normal temperature changes have no effect. I have some ST-251s (I think
that is the model) sitting at the bottom of a closet. I bet if I could
find a system today to power them up, they would work just as well as
20 years ago (if the grease hasn't congealed).

I agree, I've a few of them, WD 20Mb and a Kalok 40 Mb with Win3.11,
no defective sectors.
These disks never die.
 
R

Rick

Jan 1, 1970
0
William said:
Hi!


Good points, all of them. Checking to be sure that the system's CMOS battery
is still running would be an excellent idea. After years of sitting it could
be dead or depleted. (Many older motherboards used a rechargeable NiCad
"accordion pack" battery.) If yours has a battery like this, leaving the
system powered on overnight might bring it back up. They do seem to be
pretty robust.


Be ***very*** careful if you do this! If you can help it, do *not* remove
those hard drives from the system unit. ST-251 drives have stepper motor
head actuators that are subject to falling out of calibration with the
information stored on the drive platters if the operating temperature range
changes or the drive is removed and reinstalled. There are only two ways out
of this if you get the drives working--either hope that you can find the
right climate/installation "sweet spot" or low-level formatting. Low level
formatting will destroy all data on the drives.

William

That's not the way I understand the technical problem. Physical removal
of the drive doesn't do anything. It's actually operation of the drive
that can eventually cause problems. Considering how much heat these
drives generate during operation simple temperature changes from
removal/reinstallation aren't going to cause the problem.

Because the stepper motors aren't all that accurate for head placement,
over time data is written not quite exactly in the same position on the
physical tracks. If the variance is bad enough over time you can start
getting "sector not found" errors and the like if the write position for
the data gets too far out of alignment with the servo tracks. It can
start crapping out the servo tracks in the process - making head
placement impossible.

The cure is to just perform a low level format on MFM drives with
stepper motor head actuators every few years as part of routine
maintenance, rather than wait for read or write errors to start
happening. And, of course, back it up and make sure you have a reliable
restore procedure before doing this.

The problem does not apply to MFM drives with voice coil head actuators.

Rick
 
F

Franc Zabkar

Jan 1, 1970
0
Sam Goldwasser wrote:

Hi...

Anyone else remember "stiction" ?

Take care.

Ken

The following article suggests that stiction is a problem that first
appeared in 3.5" drives.

http://en.wikipedia.org/wiki/Stiction#Stiction_and_computer_maintenance

"In the context of hard disk drives, stiction refers to the tendency
of read/write heads to stick to the platters, preventing the disk from
spinning up and possibly causing physical damage to the media. Some
hard drives avoid the problem by not resting the heads on the
recording surfaces.

Stiction is also known to cause read/write heads to stick the platters
of the hard drive due to the breakdown of lubricants which coat the
platters themselves. In the late 1980s and early 1990s as the size of
hard drive platters decreased from the older 8" and 5.25" sizes to
3.5" and smaller, manufacturers continued to use the same calendering
processes and lubricants that they had used on the older, larger
drives. The much tighter space caused much higher internal operating
temperatures in these newer smaller drives, often leading to an
accelerated breakdown of the surface lubricants into their much
stickier components."

- Franc Zabkar
 
S

Sam Goldwasser

Jan 1, 1970
0
Ken Weitzel said:
Hi...

Anyone else remember "stiction" ?

Yep, been there done that. :) A good whack on one corner was one method!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.
 
T

**THE-RFI-EMI-GUY**

Jan 1, 1970
0
If you want a gentler solution, spin the drive on its axis before
booting up. I had a Zenith portable that had stiction and that solution
worked every time.

Sam said:
Yep, been there done that. :) A good whack on one corner was one method!

--- sam | Sci.Electronics.Repair FAQ: http://www.repairfaq.org/
Repair | Main Table of Contents: http://www.repairfaq.org/REPAIR/
+Lasers | Sam's Laser FAQ: http://www.repairfaq.org/sam/lasersam.htm
| Mirror Sites: http://www.repairfaq.org/REPAIR/F_mirror.html

Important: Anything sent to the email address in the message header above is
ignored unless my full name AND either lasers or electronics is included in the
subject line. Or, you can contact me via the Feedback Form in the FAQs.

--
Joe Leikhim K4SAT
"The RFI-EMI-GUY"©

"Treason doth never prosper: what's the reason?
For if it prosper, none dare call it treason."

"Follow The Money" ;-P
 
J

James Sweet

Jan 1, 1970
0
Can you cite a reference? In my experience, MFM drives are about the
most robust things on the Planet. :) The tracks are so far apart that
normal temperature changes have no effect. I have some ST-251s (I think
that is the model) sitting at the bottom of a closet. I bet if I could
find a system today to power them up, they would work just as well as
20 years ago (if the grease hasn't congealed).
I used to have a 286 with one of those, I used it for years after
removing the cover to break free stiction so it would spin up and it
never failed.

Unfortunately the similar 30MB RLL drive in my PC/XT died, I dragged it
out of long term storage in my mom's shed and it makes some unhealthy
noises and won't boot :(
 
J

James Sweet

Jan 1, 1970
0
Geoffrey said:
Sure. It started out on 40meg Quantum brand 3.5inch SCSI drives. Due to the
quickly changing technology, Quantum got as far as the LPS (Low power) 105 meg
drives before they found out about the problem and replaced the grease.

I've heard of a few 20 meg drives having it, but have never seen one.

Where there other manufacuters?

As far as I know, it never affected MFM/RLL/IDE drives.

That was in the early 1990's. By now, most drives of that age of any
type and manufacturer may be afflicted by it.

Geoff.


Stiction was caused by the read/write heads getting stuck to the disk
surface. For years I had an open 20MB Seagate SCSI drive sitting on my
bookshelf, one day I rotated the platter by hand and it ripped a couple
of the heads right off the arms, they were stuck quite firmly to the
disc. Oops!
 
C

clifto

Jan 1, 1970
0
**THE-RFI-EMI-GUY** said:
If you want a gentler solution, spin the drive on its axis before
booting up. I had a Zenith portable that had stiction and that solution
worked every time.

I also remember (but never tried) the idea of putting the drive in the
freezer for a while in a plastic bag and letting the temperature change
do the work. (The plastic bag was to reduce condensation on the drive
itself.)
 
C

clifto

Jan 1, 1970
0
I need to find at least one MFM HDD/floppy controller card to try to
get into my old system. My billing files and some other programs which
I would like to back up are on on these drives. I think my controller
failed. I could really use another of these drives if anyone has one
also but if not I would be happy just to find a controller board
initially. I'm running two Seagate St251 drives.

You're sure it was MFM? The 251's were often used with RLL controllers.
 
J

James Sweet

Jan 1, 1970
0
clifto said:
You're sure it was MFM? The 251's were often used with RLL controllers.


People often "cheated" and used MFM drives with RLL controllers, but the
ST-251 was designed as a 40MB MFM hard drive. It was original equipment
in the IBM AT.
 
S

Stan Blazejewski

Jan 1, 1970
0
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