Apple disk ][ service

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Apple disk ][ service

Hello there,

As my two Disk ][ drives were making unhappy noises, I searched the web for some instructions but the german website I often see linked on these forums is not available anymore.

 

I went ahead and serviced one unit myself, I think I was very succesfull as the unit is now quiet and happy with most of the disks it would not read before. Speed is also ok. However, it would be nice to know if there are further adjustments to be performed besides speed - I do have an oscilloscope and I can do proper soldering! :)  I see there are some trimmers on the main board - which I haven't touched of course.

 

Does anybody know is there is any more information on how to service those drives?

Thank you!

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First I'd clean up  the

First I'd clean up  the moving parts, rails and spindles and give it a new grease with a (really) little bit silicone grease.

 

After that a cleaning of the heads with IPA.

 

Maybe a recap... and do not forget: After disconnecting and reconnecting the drives the the Apple recheck the connection twice (corrcct orientation of the plug) before turning on the computer.

 

Btw, which site do you mean, that went offline?

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Hi therethis one is not

Hi there

this one is not accessible anymore: http://www.appleii-box.de/H084_1_AppleIIDiskService4.htm

I have done exactly as you say and indeed I used a very tiny amount of silicone grease. One of the drive had a hard to turn bearing in the white plastic wheel that goes in the disk core - that's now sorted and it's working ok. 

 

Yes, when I was a kid my brother plugged one of those cables incorrectly and a magic smoke came out. I marked all the connectors before removing them and triple-checked them afterwards!

All connectors cleaned with contact cleaner and head with IPA.

I just found this though: http://www.harrowalsh.de/Elektronik/APPLEBOX/appleboxdiskiipage1.htm

 

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Thanks Tom!This is the same

Thanks Tom!

This is the same content I had found earlier on so happy days. Indeed I basically followed what they say. I am not sure about drive speed as I get slightly different speeds by following different methods - and my speeds are not "rock solid" as in their pictures using Locksmith, but not by a lot.

Eventually the second drive refused to work properly after cleaning it: when I tested it, the tracking wheel seemed stuck. I disassembled it again and all seemed ok but once reassembled it was working again. The alignment software (DataLife Drive Analyzer) tells me that all is good with the drives. I may want to check what's going on with the oscilloscope one day and also replace all the capacitors.

For now all seems well, no more squeaky noises and no more "stuck" disks. 

Is there a known source for those belts? They seem in good shape but again they must be old!

Thanks all!

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pcbastler wrote:First I'd
pcbastler wrote:

First I'd clean up  the moving parts, rails and spindles and give it a new grease with a (really) little bit silicone grease.

 

After that a cleaning of the heads with IPA.

 

Maybe a recap... and do not forget: After disconnecting and reconnecting the drives the the Apple recheck the connection twice (corrcct orientation of the plug) before tu

 

 

For the record, I have never seen a Disk ][ where it was physically possible to insert the cable backwards. It is certainly possible to mis-align it, but the notch on the cable prevents it being flush with the Disk ][ controller, thus, unless you force it on, bending pins in the process, that should not be an issue. Checking for mis-alignment though, is crucial. As to the OP, it'd help to see a viedo of what is wrong with the drives.
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Hi Timelord,Indeed, I

Hi Timelord,

Indeed, I remember the connector was misaligned when the drive went up in smoke.

The drives are both ok now. I have tested them at length with various software and I do not see issues. The Apple works fine. Only, sometimes it fails to boot or does weird things. But usually once it's booted up it's fine.

I still haven't cleaned the board and re-seated all the chips so hopefully it's just that.

 

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One of my drives makes a

One of my drives makes a whining noise, not too loud, not always. I thought it could have been a bearing but it turns out to the the disk rubbing on the head or on the little spongy thing that applies pressure on the other side. If I manually lift the spring-loaded arm with a non-conductive tool while the disk spins and while it's making the noise, the whining noise goes away.

The head is clean and I rubbed that spongy thing with IPA too. Can anybody think of anything to fix that issue?

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tony359 wrote:One of my
tony359 wrote:

One of my drives makes a whining noise, not too loud, not always. I thought it could have been a bearing but it turns out to the the disk rubbing on the head or on the little spongy thing that applies pressure on the other side. If I manually lift the spring-loaded arm with a non-conductive tool while the disk spins and while it's making the noise, the whining noise goes away.

The head is

 

Which exact mechanism do you have, and is this with all diskettes, or just some?

 

That will alsbolutely happen if for instance, you use HD media in a DD drive. Otherwise, it could be two or three things, depending on the drive type and the mechanism used. Post photos if you aren't sure. 

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Here is a video of the noise.

Here is a video of the noise. As you can hear in the background, ProDOS is being loaded fine. After this, I lifted the arm with the felt, brushed it with a cotton bud and some IPA and it stopped. It hasn't done that again but I had brushed it before.

 

https://www.youtube.com/watch?v=llGr7zYORT4

 

The disk has a custom label on it but behind it there is an original Apple ][ label so I suppose it's fine.

Please note that the whining noise stops when I lift the arm with the felt pad. So I doubt it's a bearing or the belt or anything else.

 

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Right, one of my drives has

Right, one of my drives has an intermittent issue. I've seen it many times but every time I opened the unit to take a look it was working again. 

 

This time, it seems that the stepper motor responsible for the head movement, does not work - well, you see the head doing the usual "jerking" movement when starting up but the head itself does not move the the outer end of the disk first. As a test, I manually moved the plastic disk to move the head in the middle of the disk and then powered up the Apple: the head did the jerking movement but nothing else.

 

https://www.youtube.com/watch?v=podtqHB8yOU 

 

Yesterday I replaced all the capacitors on this unit but afterwards it was working fine. I tested it thoroughly, adjusted the speed and read and wrote many disks to make sure it was happy. I have also recapped the other drive I have and it's fine.

 

Would anybody be able to point me to the right direction? I would exclude a mechanical issue as the head "does something". I believe the small board at the back of the unit is responsible for all the motors? 

 

Thanks!

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tony359 wrote:Right, one of
tony359 wrote:

Right, one of my drives has an intermittent issue. I've seen it many times but every time I opened the unit to take a look it was working again. 

 

This time, it seems that the stepper motor responsible for the head movement, does not work - well, you see the head doing the usual "jerking" movement when starting up but the head itself does not move the the outer end of the

 

Try swapping the 2003 (D4). This controls head movement.

SAMS Disk II Service

 

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Thanks, that manual is great!

Thanks, that manual is great! Too bad an alignment disk is required for the most cool stuff! But now I have a place where to start.

 

The other drive keeps whining at times - you did say there may be a few causes depending on the flavour of the unit?

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Hi Timelord, I have swapped

Hi Timelord,

 

I have swapped the 2003 with the one from the other drive and it's working now, thank you! I have ordered a replacement. This drive has been working intermittenly over the past week or so, I'm glad that it died and that we found the issue!

I probed the faulty one and it seems that one of the lines going to the stepper motor was dead. That may explain the jerky movement but nothing more.

 

It's curious that when I pulled the working one out of its socket it was quite dirty, probably some form of oxidation.  It cleaned well with alcohol and fiber pen though. 

 

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Use an engineering eraser

Use an engineering eraser block on the pins. Chances are that one of them has internal rot. Check continuity between the leg, and the attachment point on the top. If there is internal rot, then you will lose continuity along the full pin length. 

 

In that case, you can carefully graft a new leg to the IC, although this could indicate rot developing in the other pins. It usually isn't worth fixing such a cheap and common part, but I usually save them in case I need one in a pinch, even if that means re-pinning it. 

 

If all of the pins have continuity along their full length, then either the oxidation was creating resistance, or the internal connection to the pin is burnt out. 

 

You can test disk speed without a speed test disk, usiing the appropriate type of probe lamp. The drive spindle is designed to allow you to visually set the speed. 

 

As for the whining, it'd help me to diagnose iit if you can produce a short video clip of what is happening, and if it only does this with a disk inserted, or if it does it whenever the drive spins. If it is from media only, then it might be that you need to adust (or replace) your collet hub, or replace the head load pad. 

 

Run the drive as open as possible, so that you can view the media as it spins. Be careful not to short the analogue board in the process. If the disk media is not flat as it passes under the head, then there is a pressure issue (and you are damaging the media).

 

I'll attach the Chilton guide, as it covers these procedures.

Chilton Disk II Repair

 

Note: The scan quality of this is poor. The procedure differs for the UniDisk and DuoDisk series mechanisms.

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Hey Timelord, The darkened

Hey Timelord,

 

The darkened chip is the working one! :) I managed to clean it fully with a fiber pen and some alcohol. As you say these are very cheap and there is no point in wasting time on those.

 

Regarding the whining, I posted the details you asked me a few posts above. But I didn't remove the analogue board. The whining stops when the pad arm is manually lifted so that tells us it's not a bearing or the spindle or the motor. Hence I do not think it is the collet hub - which I have fully cleaned and lubricated BTW. 

I feel it's either the pad or the head itself. But right now the drive is not whining anymore... So I'll keep an eye on it and follow up.

 

Great document, again. Too bad most pages seem to be missing at the end?

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tony359 wrote:Hey Timelord,
tony359 wrote:

Hey Timelord,

 

The darkened chip is the working one! :) I managed to clean it fully with a fiber pen and some alcohol. As you say these are very cheap and there is no point in wasting time on those.

 

Regarding the whining, I posted the details you asked me a few posts above. But I didn't remove the analogue board. The whining stops when the pad arm is manuall

 

 

That as I recall, is an excerpt from a SAMS book for the Apple II in general. Most of the SAMS books are fully digitised and available on Asimov and Apple2.org.

 

...

 

https://mirrors.apple2.org.za/Apple%20II%20Documentation%20Project/Books/

 

https://ftp.apple.asimov.net/documentation/hardware/

 

There are also quite a few other places to find them all. Some are available from the USLOC at archive.org, some are on various sites such as reactivemicro, although Brian's downloads section seems to be down right now. 

 

 

https://apple2online.com/index.php?p=1_2_Documentation-Library

 

https://apple2online.com/index.php?p=1_48_Technical-Notes-Procedures-Manuals

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Today I received the

Today I received the replacement 2003 ICs. I've also cleaned and reseated all the chips on both drives. They both work flawlessly now! That drive had been intermittently failing since I got the machine and it was so frustrating as I thought it was the disks and every time I was opening to take a look it would start working again! :)

 

Regarding the whining sound, I have inspected the pads and the one making intermittent whining noise is a bit yellowish - I tried rinsing it with some Isopropyl - without removing it, I don't want to play with 40 years old plastic and if that snaps the drive is gone - and we shall see how it goes. It does not look worn out, in fact it seems less worn out than the other drive's. 

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I have to withdraw my

I have to withdraw my statement here. I have the same exact issue but now it's on the other drive - I swapped them on the I/O board so I could boot from the one which was giving issues. 

 

Shall I assume a Disk ][ card issue then? 

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Right, so I may have found

Right, so I may have found the culprit. Sorry for the many updates.

 

I removed all the ICs from the Disk ][ card, cleaned, sprayed contact cleaner and re-seated. Also re-did the connector solder joints. I still had the same issue.

So then I swapped the cables at the card and the issue moved to the other drive.

I then swapped the cables at the drives and the issue moved again.

 

So I disassembled the terminal crimps, cut a centimeter of flat cable and crimped again.

 

Right now, they both work. But I've seen that before so we shall see :) 

 

An issue with the cable would make sense as every time I disassembled the drive, it started working again - obviously the cable gets some movement when doing that. Finger crossed :) 

 

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Quick update and a question.

Quick update and a question.

 

It finally seems that both drives are now working reliably after I crimped again one of the cables. That intermittent issue had plagued me since I got the machine!!

While checking for drive speeds, I noticed it doesn't seem to be very stable and according to SpeedyG documents that indicates an issue. I was thinking of replacing the belts as they are indeed 40 years old - even though they look in good shape. But all my searches did not show a precise measurement or type.

Can anybody help me in finding new belts for my ][ disk drives please?

 

(it's not very clear on the monitor but the average line slowly drifts towards the centre but only on one of the drives. And YES, I know that speed is too high, I have adjusted it since)

Thanks!
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Console5 has them. https:/
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Fantastic! I live in the UK

Fantastic! I live in the UK but I happen to have a parcel ready to leave to my addredd from a friend in the US so it should be doable!

 

Do you think they are going to help with the speed?

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I have some that I acquired

I have some that I acquired eclusively to measure them, but that has not made it onto my agenda yet. That said, I have a lot of these drives and I have never had to replace a belt. 

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Yeah, I saw your comment

Yeah, I saw your comment before. What's your thought on that speed graph I posted? According to SpeedyG it indicates an issue - he does mention the belts or some "compensation issue" but I couldn't find any more details.

I guess those drives have been sitting there for many years so it may be that the belts have taken the shape of the pulleys - maybe causing some instability when they travel. 

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tony359 wrote:Yeah, I saw
tony359 wrote:

Yeah, I saw your comment before. What's your thought on that speed graph I posted? According to SpeedyG it indicates an issue - he does mention the belts or some "compensation issue" but I couldn't find any more details.

I guess those drives have been sitting there for many years so it may be that the belts have taken the shape of the pulleys - maybe causing some instability when they tra

Warm them up by using them daily; see if that helps. If you ultimately need a belt, I will sell one. I bought a pair and I only need one for metrics. 

 

 

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I thought that too that by

I thought that too that by using them a bit the belt (and bearings) would get better but I've been using them daily for a couple of weeks and I do not see improvements.

Now the drives are working to be honest - no more "unable to load Prodos" screen with the head stuck! - even though I sometimes get the "noisy head" while a drive is reading. That could be a disk though, it's 40 years old stuff after all. 

Again, this is done more in a "restoration" optic rather than in a "let's make them work and go" mentality. 

In what country are you based?

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