Troubleshooting disk drive issue

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Troubleshooting disk drive issue

I have an Apple IIe that has stopped reading disks.  I was loading various disks that I had lying around to see what was on them and the system just stopped loading anything off the disk drive (duodisk).   

Here is the steps I have taken so far:

I examined the analog board but could see no obvious issues

I swapped out the duodrive for another duodrive and I am getting the same issue.

I also tried 3 different unidisks and one worked once but then stopped loading again

All the drives have the led come on, the motor clicks, but the read/write head doesnt seem to move or try to read the disks

I tried cleaning the head on one of the drives but didnt change anything.

I swapped out the disk controller card and that did not change anything

I also hooked up a Disk II with a controller card and that worked yesterday but I tried hooking it up again today and disks no longer load. 

Disks can load from my FLoppy EMU.  

All of the drives were known to work before this (one had alignment issues) 

I ran the self diagnostics and comes back System Good  

 

Can anyone help guide me in the right direction as to what to look for as a repair?

My skill level is low so any advice is appreciated

 

EDIT  The unidisks do work   I noticed the disks I was using to test looked like they got a scratch on them from one of the drives   Other disks do load

Both duodisks still do not operate so need to troubleshoot those

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Disk II drive issue

Hello.

 

Looks like you have swapped everything  including drives and controller.

One other test you might try.

POWER OFF!!

 

Remove all other interface cards from the Apple so you only have the Disk II controller in the computer. Try booting and see if that made any difference. Remember, floppies can go bad.  Try a few.

 

If the drives work this way,  Power down and replace one of the cards you remov ed.  Test again.  Repeat this with each card until it stops working. Don't forget to POWER DOWN when removing and replacing cards.

 

If the thing starts working again with all cards in place, great.  If that happens it may be that a bad slot connection on one of the other cards had gotten noisey and removing an d re inserting might have fixed it.

 

If you find one card appears to be the culpret, remove it, inspect, and push down any socketed chips.

 

If this doesn't reveal anything, it may be time to suspect a power supply issue.  First, re-seat the power connector and test again. Usually, the power supply works or it doesn't. But the starting of the drive motor does put a little surge on it.

 

Good luck.  Maybe someone else will have an idea.

 

Chris

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The fact that your Floppy Emu

The fact that your Floppy Emu works means your Disk II card is fine.  And the fact that both Duodisks fail to read means that something is going on with your media (perhaps)...

 

When you cleaned the disk drive heads (you used a cotton swab and isopropyl alcohol, right??) was there any residue on the swab?

 

Examine your diskettes.  On the read-side (opposite the label side) is there what appears to be a faint concentric scratch near the outer circumference of the media in the "window"?

Dirt on the swab combined with a scratch indicates that your diskettes have mould growth on them (an increasingly common problem), and during a read operation, that mould accumulated on the read/write head.  Once it accumulated, it scratched the surface of the diskette, and every subsequent diskette you inserted into the drive.  Because the drive starts reading at track zero, near the outer edge of the diskette, a scratch will usually be visible there.

Those scratched diskettes are ruined.  There is nothing you can do to save them.

Mould is difficult to detect.  It sometimes looks like a dull mottled appearance on the media.  Sometimes it's invisible.

I keep a disk drive with no cover on it for just those instances.  If I suspect mould I carefully read the diskette and then wipe the head.  If there's residue then I know that diskette has mould.

But at least I've cleaned the head and no further diskettes will get damaged.

 

It could be something else altogether.  Your drive speed could be off.  That needs to be checked.

Your alignment may be off  - that's more difficult to fix, but still doable.  It is much harder with a duodisk.  I avoid those units and prefer to use single 5.25" drives.  With single units at least you can swap them around.  Duodisks suck the big one for serviceability.

 

Anyway, hopefully this gives you something to go on.

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Looks like mold might have

Looks like mold might have been the issue.  The disks did have scratches.  I cleaned the head again very thouroghly and other disks started to load just fine.   I am taking your advice and leaving one drive open to try new disks in the future.  

Thanks for helping me figure this out.

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ekylep wrote:Looks like mold
ekylep wrote:

Looks like mold might have been the issue.  The disks did have scratches.  I cleaned the head again very thouroghly and other disks started to load just fine.   I am taking your advice and leaving one drive open to try new disks in the future.  

Thanks for helping me figure this out.

 

Mould can often be visible.  When I have a diskette I think might have mould on it due to its blotchy appearance, I do the following:

 

I slit the diskette jacket with a razor blade and carefully extract the "cookie" inside.

I then wash it with warm water and a little bit of dish soap and a soft towel.

Then I blot it dry with paper towels.  You have to be really careful because if you put a kink it it, it will be ruined.

I carefully slide it back into its jacket, and I fire up ADTPro (or more often nowadays, AppleSauce) and I read it ONCE to image it.  Having Applesauce is nice because it can record a .woz image of it even if it is copy protected. Once I have imaged it, I discard the diskette.  Even though the media is now mould free, the jacket is not mould free and in a few weeks the problem may return, so in the garbage it goes.

 

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