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View Full Version : Restoring an IBM AT 5170



Maverick1978
April 27th, 2010, 11:11 AM
Hey, folks..

Picked one up off of Craigslist about 10 days ago for $100. Cosmetically, it was in good shape, came with the old IBM Hercules Monochrome display, original 1.2mb 5.25" floppy, working spare 1.2mb 5.25" floppy, the original clicky keyboard, and a few expansion cards (2mb RAM expansion, 9600kb modem, IBM mono/parallel card, and another IBM card that I don't recognize, but appears to have BIOS chips on them - even though I also have 2 on-board)

No IBM Reference/DOS/BASIC manuals though... sadly.

It had several BIOS errors with it, first and foremost was the clock. The previous owner soldered a phone handset battery that doesn't work worth a dang, so I'll be redoing that. I managed to clear the other BIOS errors by simply reseating the "other" IBM card referenced above, but the machine still wouldn't boot as it didn't realize it had a hard drive :)

After digging up an image of the AT Diagnostics disk as well as a bootable image with GSETUP, I configured the original 31mb Seagate ST-4038 as per the type listed on the drive, which checked out with GSETUP as well (type 21, IIRC). No go. I can't even tell for sure that it's powering up, I just know that it's not booting from that hard drive.

I've another MFM controller on the way, and I've got to dig my meter from storage to test for proper voltage from the power supply.

Any other ideas? - I'd like to keep it original, but am not against putting an IDE drive in there.

Also - quick question time while I've got your attention :)

1) the floppy drive has the side rails that allow it to go sit properly in the chassis, but these rails do not have a front-facing section allowing me to secure the drive in there - right now, it can be pulled in and out easily. Anyone got some proper side rails they'd be willing to part with?

2) from what I've seen online, this machine normally came with EGA from the factory... is that correct, or did I just get a unit that was downgraded for whatever reason? (not that I don't kind've like the monochrome - I grew up on that!)

Chuck(G)
April 27th, 2010, 12:28 PM
There was no "standard" display configuration for the 5170. You bought the box and specified what you wanted. MDA, CGA and EGA were all options.

Your drive rails are fine--it sounds as if you're missing the small metal angle-bracket like retainers that screw into the front of the system unit that holds the rails in place. They're easy enough to make from angle iron (either aluminum or steel) available from most hardware stores if you can't find any.

strollin
April 27th, 2010, 01:04 PM
I made some of the drive retainers for my 5170 by cutting the ends off some blank slot plates (the metal plates that cover empty slots in the chassis). I cut the end off then bent the tab over at a 90 degree angle. On the ones I used there was already a hole for a screw but on others, like the picture below, you would need to drill a hole.
http://www.strollin.net/slot_plate2.jpg
I cut off the the end just above the narrow tip. They were almost perfect replacements.

hargle
April 27th, 2010, 01:09 PM
>After digging up an image of the AT Diagnostics disk as well as a bootable image with GSETUP, I configured the original 31mb Seagate ST-4038 as per the type listed on the drive, which checked out with GSETUP as well (type 21, IIRC). No go. I can't even tell for sure that it's powering up, I just know that it's not booting from that hard drive.

You would most certainly know if the HDD is powering up. it will sound like a jet engine. :) I have never heard a quiet (like modern IDE) MFM based hard drive; part of the reason why I always opt to upgrade my old machines with modern drives. Computers should be used, not heard.

paul
April 27th, 2010, 01:13 PM
No go. I can't even tell for sure that it's powering up, I just know that it's not booting from that hard drive.

Try drive type 8. You need to provide more information for us to diagnose this. Is there nothing on the display? No hard disk startup noise or floppy seek on boot?

If you can configure the BIOS settings most things must be working.

modem7
April 27th, 2010, 11:31 PM
No go. I can't even tell for sure that it's powering up, I just know that it's not booting from that hard drive.
No 1700 series errors on screen ?


Try drive type 8.
Although type 8 would allow boot/read/write operation, the ST-4038 is technically an IBM type 20, because of the WPC of 300. Better to use type 20 than 8.

Maverick1978
April 28th, 2010, 08:57 PM
My apologies - I wasn't clear :) The computer boots from floppy just fine (I was able to load the AT Diagnostics diskette as well as a Dos v6.22 boot-disk with GSETUP on there!), it's the drive that I can't tell for sure if it's starting.

FWIW, my old 386DX-25 had a 38mb MFM drive in it. I remember it being quite loud - at least in use. I honestly can't say I remember what it sounded like starting up, however... (sad, I know!)

The 1700-series errors on screen were cleared once I configured the BIOS. Won't have time to mess with it again until at least Sunday, but will try Type 8 on it. Will hopefully have my multimeter out of storage by then as well, and can check voltage on the power connector.

As for the drive rails... I'm far from above making my own from slot-covers (the idea had struck me too!) - i was just kind've hoping to keep the machine as original as possible.... :)

Thanks for the replies, folks... will follow up with some more progress reports soon

paul
April 29th, 2010, 01:36 PM
As modem7 said it's type 20.

If the hard disk was running you would know it - it's loud. The power connector on my ST-4038 is a bit loose (same with others I've had) and that may be the issue for you, or the disks are stuck to the heads.

I doubt very much the power supply is not working since it clearly already runs the floppy drive and motherboard.

Good luck!

tezza
April 29th, 2010, 02:18 PM
I concur with the comments regarding the hard disk. It sounds like a jet engine ramping up! The first time I heard it I was sure I wasn't going to see a successful boot screen...but I did. It seems it's just the way these disks are. They sound like they mean business!

Tez

vwestlife
April 29th, 2010, 05:10 PM
You would most certainly know if the HDD is powering up. it will sound like a jet engine. :) I have never heard a quiet (like modern IDE) MFM based hard drive; part of the reason why I always opt to upgrade my old machines with modern drives. Computers should be used, not heard.

If you want to include vintage IDE drives, the little 40-megabyte ST-351A/X is pretty darn quiet, and not any louder than many modern 7200 RPM drives, including Seagate's own, before they introduced their current fluid-bearing design which basically renders the spindle motor inaudible.

Maverick1978
May 4th, 2010, 07:14 AM
Sorry for the delay - time of late has become very precious, and exceedingly rare!

I was able to spend some time with the machine last night. I pulled the hard drive and reseated all the cabling. I then pulled all the expansion cards save for the mono/printer card and the mfm controller board, booted up, ran GSETUP, and it worked correctly... with giving me a 1701 drive error :) Started adding the other expansion cards back in one at a time, and was able to maintain that level of non-working, which is a start.

I've a 2nd mfm controller board now, but the factory cables can't be used with it - I'll need to grab some spares from my old stock in storage.

With that said, I'm definitely getting some noise out of the HD now, which is good. What's not good is the amount of heat it's generating over a relatively short amount of time (powered on for ~20 minutes) - the metal enclosure on the sides and top of the casing were extremely hot to the touch. When I noticed this, I powered it down.. at this point, I don't think that the other mfm controller board will help; I don't recall my old 38mb MFM drive in my old 386 generating anywhere NEAR this type of heat, and I'm suspecting that there's a short or some other electronics problem causing it. Any ideas?

FWIW... if the electronics is anything beyond rudimentary, it's well beyond my current capabilities to properly diagnose and fix - though I'm hoping to improve those skills over the coming months.

-Mav

mikey99
May 4th, 2010, 09:57 AM
I have a 5170 AT that I recently restored back with all its original parts.

The case had been upgraded a few times , to a 386SX 16, then to a 386 25.
It eventually landed in my attic where it sat for 10 years or so until I got
it down and cleaned it up. Fortunately I still had all the original parts ,
motherboard , cards etc. I never thought 'downgrading' would be so much
fun !

paul
May 4th, 2010, 01:18 PM
...a 1701 drive error ... the amount of heat it's generating over a relatively short amount of time (powered on for ~20 minutes) - the metal enclosure on the sides and top of the casing were extremely hot to the touch.

It's probably OK, they do run a bit warm and any failure would likely shut it down (or the PS.)

Have you checked that the Drive Select setting on the hard disk is on the second jumper setting (assuming the data [larger cable] has a twist in it)? Are you sure the data cable is for a hard disk and not a floppy disk? I doubt the AT controller board has failed. I would be checking the drive type again and although I've never used GSETUP I would inclined to try the normal IBM AT setup diskette.

tezza
May 4th, 2010, 04:51 PM
I found GSETUP worked fine for my AT, when I was going through the setup process on my AT (http://www.classic-computers.org.nz/blog/2009-08-17-reviving%20an-IBM-AT--bios-and-hard-disk-setup.html). However, if you have the original setup program though, even better.

Good luck with it. The AT's are awesome beasts! At least in size and weight! :)

Tez

Floppies_only
May 4th, 2010, 05:00 PM
There was no "standard" display configuration for the 5170. You bought the box and specified what you wanted. MDA, CGA and EGA were all options.

Your drive rails are fine--it sounds as if you're missing the small metal angle-bracket like retainers that screw into the front of the system unit that holds the rails in place. They're easy enough to make from angle iron (either aluminum or steel) available from most hardware stores if you can't find any.

The AT "Installation and Setup" manual (there's one on ebay right now) will show a line drawing of this piece of metal.

Sean

Floppies_only
May 4th, 2010, 05:06 PM
...although I've never used GSETUP I would inclined to try the normal IBM AT setup diskette.

Is it possible to make a copy of the IBM setup diskette with DOS?

Thanks,
Sean

modem7
May 4th, 2010, 11:51 PM
(assuming the data [larger cable] has a twist in it)?
"Data" should be "control".

modem7
May 4th, 2010, 11:53 PM
Is it possible to make a copy of the IBM setup diskette with DOS?
The 'Diagnostics for IBM Personal Computer AT' diskette will be what's referred to. It has a 'SETUP' option in the menu.

The diskette is a standard 360K one. You can use DISKCOPY to copy it (via a 360K drive).

modem7
May 4th, 2010, 11:55 PM
With that said, I'm definitely getting some noise out of the HD now, which is good. What's not good is the amount of heat it's generating over a relatively short amount of time (powered on for ~20 minutes) - the metal enclosure on the sides and top of the casing were extremely hot to the touch. When I noticed this, I powered it down.. at this point, I don't think that the other mfm controller board will help; I don't recall my old 38mb MFM drive in my old 386 generating anywhere NEAR this type of heat, and I'm suspecting that there's a short or some other electronics problem causing it. Any ideas?
In a room at about 20 degrees C, I started up my (working) ST-4038. After 15 minutes, the metalwork on the drive was no longer cold, but had not even reached warm (my definition of 'warm'). After 30 minutes, the drive was warm. So you've definitely got a faulty drive.

Maybe the grease on the spindle bearings has deteriorated too much. In that situation, I've had success with WD40. Short term solution only. A bearing-noisy ST-412 that I treated about a year ago had to be retreated recently.

Chuck(G)
May 5th, 2010, 09:28 AM
You may want to try using some real lubricant, rather than WD-40, which is pretty much Stoddard solvent and not much more. White lithium grease comes in an aerosol form and may give you more lasting performance. I use it on noisy fan bearings quite a bit with very good results.

Maverick1978
May 5th, 2010, 02:43 PM
@Mikey99, Was that 386 upgrade from an inboard? Wanna part with it? :) Might be interesting to have a 2-in-1 machine, so to speak!

@Paul, I'll double-check the drive jumper settings. So far as the cabling, the cables are original IBM and are labeled with Drive letters. It's definitely on a hard drive cable.

@tezza, I've been through your site on a few different occasions, and had seen your restorations on both the IBM AT and C= SX64 (which, sadly, I haven't even had time to open mine and blow out any dust before powering on!) - great site, and informative. I'm glad that you decided to chronicle your adventures :)

@floppies_only, I don't have the original manuals or diskettes with my AT, unfortunately, though I'm on the lookout for them. I downloaded an image of the AT diskette from a site I found in a Google search as well as a bootable-diskette with GSETUP on it. I wrote both out, but opted for GSETUP for the GUI interface, and most especially because all of the drive types were displayed and you can cycle through them.

@modem7, I'm not hearing the spindles turn in the drive. I hear the read/write head moving during initialization and that's about it. How would one go about lubricating these? I've never had an MFM drive apart - have never even removed the logic boards. I just know that this thing gets almost too hot to touch very quickly. I expect a drive to be warm, even hot - just not too hot to touch.

mikey99
May 5th, 2010, 07:46 PM
@Mikey99, Was that 386 upgrade from an inboard? Wanna part with it? :) Might be interesting to have a 2-in-1 machine, so to speak!



No, It was just a clone 386-25 motherboard, and unfortunately I left the batteries in the AT and it leaked electrolyte
on the MB. The 386 MB still works but the clock wont retain its setting when you power off the system. Probably
just a corroded land but haven't had time to troubleshoot that.

paul
May 5th, 2010, 08:00 PM
I just know that this thing gets almost too hot to touch very quickly. I expect a drive to be warm, even hot - just not too hot to touch.Measuring the current draw on the 5 and 12 V lines would be useful.

modem7
May 6th, 2010, 12:53 AM
@modem7, I'm not hearing the spindles turn in the drive.
Okay. I enterpreted your "With that said, I'm definitely getting some noise out of the HD now, which is good." as the spindle turning, even if not properly turning.


I hear the read/write head moving during initialization and that's about it.
Odd. The drive's logic board normally won't move the heads until it knows that the spindle is up-to-speed. And the board knows that from sensors. Even the ST-412 drive in the 5160 does that.


On the assumption that the spindle isn't turning, have you heard of head stiction? It's where the heads become stuck to the platters. Quite common. Search these forums for techniques that can be used to detach the heads from the platters. Observe the warnings - too much force can result in damage.


How would one go about lubricating these? I've never had an MFM drive apart - have never even removed the logic boards.

FOR ST-4038 ONLY

WARNING: In the procedure that follows, the spindle will be revealed. If the problem you have is head stiction rather than lack of lubrication, manually forcing the spindle to rotate could rip the heads off their arms.

To prevent static damage to semiconductor devices, use anti-static procedures during the following.

1. Turn drive upside down.

2. Remove the 4 Torx screws (T-10) that secure the logic board.

3. Orientate the drive so that the front is towards you (e.g. connectors for control/data cables at rear).

4. On the right side of the logic board is a 22 pin plug/socket (like the type found on 3.5" diskette drives). Remove the plug from the socket. To facilitate that action, move the logic board to the left as far as it comfortably goes.

5. The previous step allows the right side of the board to be raised by about a centimeter. Raise the right side by that amount so that it clears the metal frame.

6. On the right side of the logic board, there is an 8-pin plug/socket. Now that the right side of the board is slightly raised, remove the plug from the socket.

[ Note: the right side of the board is now free and can be raised up to a few centimeters. ]

7. On the left side of the logic board is a 34 pin plug/socket. Remove the plug from the socket.

8. On the left side of the logic board is a 6 pin plug/socket. Remove the plug from the socket.

9. The logic board is now free. Put it in a safe place.

[ One end of the spindle is revealed. You'll see a flat copper bar that connects the center of the spindle to the drive chassis. It's purpose is to ground the spindle (well, make the spindle the same potential as the chassis). ]

10. Remove the spindle grounding bar (one Torx screw of size T-7).

11. On the end of the spindle that you can see, there are two small holes near the center. Those holes are where I would inject liberal amounts of (non-conductive) liquid lubricant. I would then tip/turn the drive through various orientations to ensure that the lubricant gets into the crevice that leads to the bearings.

12. Leave drive alone (upside down) for many hours before reassembly. That allows time for the lubricant to get where it may need to get to. Probably good to place drive on something that will catch any leaking lubricant.