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Tandon TM-100-2A on 5150 - grunting sounds

phreakindee

Experienced Member
Joined
Aug 4, 2008
Messages
144
Location
Western North Carolina
Having trouble with one of my TM-100-2A drives on my PC 5150. When I first got it, all it did was make a loud grunting noise, like it was trying to read but couldn't move or something. I took it apart a bit, cleaned up what I was comfortable with, and it started working. But then after about 4 or 5 disks it started all over again. It will read the disk directory with the DIR command, but anything more and it will start to load a program and give a sector not found error, asking A,R,Ignore. If I open it up again and move the head assembly a little, it seems to work for a bit, then reverts back to the grunting sounds and no loading. Ideas? Really new at these particular drives. Thanks.
 
I've been messing with a few Tandons myself, over the past week.
I'd suggest cleaning the heads, and cleaning/lubing the rails.
After that, it's probably alignment or something else requiring more work.

Sams Computerfacts may be helpful.
You can get a copy of the Sams in this thread: http://www.vintage-computer.com/vcforum/showthread.php?t=17048&highlight=Sams+Tandon&page=2

That is about the extent of my knowledge, and what I have done so far. When it comes to alignment, spindle speeds etc, I don't really have any experience or tools to do that. Really don't want to make it worse either - at this point unless it's sounding like something obvious, I'll probably just leave it alone until I can hopefully get it repaired..
 
That is about the extent of my knowledge, and what I have done so far. When it comes to alignment, spindle speeds etc, I don't really have any experience or tools to do that. Really don't want to make it worse either - at this point unless it's sounding like something obvious, I'll probably just leave it alone until I can hopefully get it repaired..

Since it does read correctly when it's working, I don't think the head alginement or motor speed have to be ajusted.

I had similar problems with my IBM 5160 XT, and here is how I did fix it:

  1. Open the chassis of the computer
  2. Locate the failing drive
  3. Unscrew the two screws holding the top PCB to the drive
  4. Disconnect P5 and P6 (write down their locations first)
  5. Gently slide the PCB forwards a little, and you should be able to lift it off
  6. Take a q-tip, and apply a little amount of alcohol to it (make sure the alcohol doesn't drip from the q-tip)
  7. Use this q-tip and 'clean' the two metal tracks the head is connected to. You should first wash one side, then slide the head manually over to the clean side in order to clean the other side of the tracks
  8. Apply some lubricating on the tracks, and move the head manually to spread it out. I used thinn oil, but better solutions exist
  9. Insert the PCB, by placing it in it's tracks and sliding it into it's original position
  10. Reattach P5 and P6, and insert the two screws
  11. Close the chassis of the computer
  12. Try to boot the drive at least three times

It should work perfectly after that. I had to boot two times before it worked, but after that, It has been working every single time. You will also notice that the drive got another, more silent "sound" when seeking.

If it doesn't work, your stepper-motor may need lubricating.
 
Since it does read correctly when it's working, I don't think the head alginement or motor speed have to be ajusted.

I had similar problems with my IBM 5160 XT, and here is how I did fix it:

  1. Open the chassis of the computer
  2. Locate the failing drive
  3. Unscrew the two screws holding the top PCB to the drive
  4. Disconnect P5 and P6 (write down their locations first)
  5. Gently slide the PCB forwards a little, and you should be able to lift it off
  6. Take a q-tip, and apply a little amount of alcohol to it (make sure the alcohol doesn't drip from the q-tip)
  7. Use this q-tip and 'clean' the two metal tracks the head is connected to. You should first wash one side, then slide the head manually over to the clean side in order to clean the other side of the tracks
  8. Apply some lubricating on the tracks, and move the head manually to spread it out. I used thinn oil, but better solutions exist
  9. Insert the PCB, by placing it in it's tracks and sliding it into it's original position
  10. Reattach P5 and P6, and insert the two screws
  11. Close the chassis of the computer
  12. Try to boot the drive at least three times

It should work perfectly after that. I had to boot two times before it worked, but after that, It has been working every single time. You will also notice that the drive got another, more silent "sound" when seeking.

If it doesn't work, your stepper-motor may need lubricating.

I will be trying this again, which is what I did minus the lubrication. It helped temporarily, but got mucked up again and now won't even read a DIR all the time. Question: is the head assembly supposed to have a "smooth" feeling of movement back and forth along the tracks when moving it manually? It almost won't budge when I try to move it, kind of "clicks" around. Thanks!
 
Sounds like you cleaned the rails so well there is no lubrication
left :)

I would try adding a very small amount of lubrication on the rails.
Spray silicone works best, but DONT spray it on the rails.
Spray a small amount on a Q-tip , rub that on the rails ,
and slide the head assembly.

I bought a huge can of the CRC Silicone Spray at Wal Mart
in the automotive section for $2
 
Sounds like you cleaned the rails so well there is no lubrication
left :)

I would try adding a very small amount of lubrication on the rails.
Spray silicone works best, but DONT spray it on the rails.
Spray a small amount on a Q-tip , rub that on the rails ,
and slide the head assembly.

Yup, considered that after the fact! Just lubed them, doing just that... but nothing, though it does sound a bit quieter. Still no DIR readings, nothing just "Sector not found error", and at first there was the loud grunting again, 5 grunts and then it gave an error. Now it's just quietly giving errors
 
There was another discussion in the forum about TM100
http://www.vintage-computer.com/vcforum/showthread.php?t=17048

...... and there is a service manual available here :

http://members.dodo.com.au/~slappanel555/manuals/Tandon_TM100-2.pdf

Looking on page 11 of the PDF file, theres a picture that shows two
guide rails. Did you lube both of these ? The lube needs to work its
way into those plastic guides that slide on the rails. Another possibility
is the motor/mechanism that moves the heads. If possible look at the
bottom of the drive while its trying to read a diskette.... and see if anything
appears to be binding .
 
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There was another discussion in the forum about TM100
http://www.vintage-computer.com/vcforum/showthread.php?t=17048

...... and there is a service manual available here :

http://members.dodo.com.au/~slappanel555/manuals/Tandon_TM100-2.pdf

Looking on page 11 of the PDF file, theres a picture that shows two
guide rails. Did you lube both of these ?

The two that the head assembly rides on, yes.

It seems I can get a DIR reading after re-positioning the head assembly to the rear of the drive, and once I start it up it reads that fine. But when I try to load a program, it will give those 5 grunts, a read error, and then it won't even read a DIR. Same process starts all over again when I reposition the head assembly to the rear and restart. Most of the time.
 
How old are the disks that you are using?
If the heads gunk up after only a few uses, I'd get the data off those disks and onto some new ones asap.
 
Another possibility
is the motor/mechanism that moves the heads. If possible look at the
bottom of the drive while its trying to read a diskette.... and see if anything
appears to be binding .

On looking underneath, the drive motor is working fine, spinning the disk and all of that. The head position motor however is not really moving anything, other than the assembly itself when I move the assembly out of position. Occasionally you will see movement underneath, when it actually reads a directory or a program. But this is quite uncommon still, and does not seem to be tied to anything I do. Sometimes it works sometimes it does not.

All it will really do is move the head assembly back to the rear of the drive, and sit there.
 
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The two that the head assembly rides on, yes.

It seems I can get a DIR reading after re-positioning the head assembly to the rear of the drive, and once I start it up it reads that fine. But when I try to load a program, it will give those 5 grunts, a read error, and then it won't even read a DIR. Same process starts all over again when I reposition the head assembly to the rear and restart. Most of the time.

It absolutely sounds like something is sticking somewhere. Does it stick when the head is at a spesific location, or does it happen randomly? In the first cause, where does the head assembly tend to stick?

Maybe you could try to lubricate the motor, or the mechanics between the motor and the head assembly. It should move with about the force equal to pushing a pushbutton, and it should go in "chunck"s (as in your cause).
 
It absolutely sounds like something is sticking somewhere. Does it stick when the head is at a spesific location, or does it happen randomly? In the first cause, where does the head assembly tend to stick?

Maybe you could try to lubricate the motor, or the mechanics between the motor and the head assembly. It should move with about the force equal to pushing a pushbutton, and it should go in "chunck"s (as in your cause).

It tends to stick right at the rear of the drive, up against the little screw that presses up against the back of the head assembly at the rear of the drive (it's marked with red paint in mine).
How would I get to the motor mechanics to lube those? I didn't see anywhere to get down there, without dismantling most of the drive.
And that sounds about right now, as far as force needed to move it.
 
It tends to stick right at the rear of the drive, up against the little screw that presses up against the back of the head assembly at the rear of the drive (it's marked with red paint in mine).
How would I get to the motor mechanics to lube those? I didn't see anywhere to get down there, without dismantling most of the drive.
And that sounds about right now, as far as force needed to move it.

What did you use to lubricate it? and how much did you have on it?

Anyways, try to lubricate any joints between the motor and the head assembly.
 
What did you use to lubricate it? and how much did you have on it?

Anyways, try to lubricate any joints between the motor and the head assembly.

It didn't have a name, it's a cleaning kit that I got recently for old computers, comes with disk cleaning solution, little application swabs and spray bottle of parts lubricator. Doesn't even seem to have a real brand, maybe 3M. I just put a Q-tip head's amount on each half of each rail, moves pretty smoothly now. Just still doesn't work.


I'm about to just give up, at least for now, as I've put too many hours into this already. I have another drive on the way that should hopefully work for the time being (a Mitsubishi) but I'd still like to get this Tandon fixed sometime, by someone who knows what they're doing. It's really annoying me. I'd love to figure out how to fix these things myself, but just don't have time at the moment.
 
Have you checked out the home sensor? it could be dead or just obscured by dirt. Drive tries to initialise & can't????
it's IR so you'll only be able to check it out by testing across the reciever with a meter, and putting something in the way, see if the voltage changes by a reasonable amount. I can't remember how much a reasonable amount is, but most similar sensors seem to go <1 to >4 V someone else may confirm.
 
Here's a quick check to see if there's something wrong with your positioner.

Move the head assembly until it's at its innermost (closest tot he hub) position. Reboot the system and do a DIR.

Does the head assembly move to the outermost position? If not, there's the problem. Does the head assembly move even part way to the outermost position? If so, then the likely cause is mechanical. If not, then its time to suspect the positioner (stepper) motor itself and its associated driver circuitry.
 
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