Generic 5.25" disk drives

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Generic 5.25" disk drives

Awhile back I picked up this pair of non-working generic 5.25" disk drives in a lot of Apple II equipment. I don't know much about them but was wondering if any of you have worked on similar units?

My other drives are Disk ][s.   I've cleaned the heads on these but they still won't read any disks. Not sure how much effort is worth diagnosing these and I assume there's 

nothing special about them?

 

 

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Interesting. After market drives. Try lubing.

Unlike the apple II drives that I didn't realize did nto need lube. The full height drives. I'm wondernig of they are more like PC drives and thus under the circuit board you have  a bar and it collects dust bunnies. I would have to clean the rails off and put a tad bit of lube on them.  That is assumed the drives light up and try to read the disks.

 

Thanks,

 

Josh

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My other drives are Disk ][s.

My other drives are Disk ][s.   I've cleaned the heads on these but they still won't read any disks. Not sure how much effort is worth diagnosing these and I assume there's 

nothing special about them?

What are the symptoms of the drives? Can you remove the cover and inspect the drive while it's attempting to read? Under the top board and under the disk you will see a white-ish plastic disk which is responsible for moving the head. Do you see that moving like in the video below?

The next thing you should check is the speed: using a diagnostic software (Copy2Plus will do) will allow you to check the disk speed - you'll need to boot the system somehow though :) 

 

Let us know :) 

 

https://www.youtube.com/watch?v=-FJMojuU33g

css
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Well, I'm trying to get a

Well, I'm trying to get a pair of these generic drives to work as well as a pair of disk ][ drives and not one of the four are reading any disks. 

The drive led light comes on and stays solid and the disks just spin in the drive.

 

Here's short video of the top and bottom of the drives:

 

https://drive.google.com/file/d/1GSTQlsyvNunmNQT_8KpVXnO8t0dYaCMF/view?usp=sharing

 

https://drive.google.com/file/d/1GXYBbi-jSmgAbJXZY9--wPYnMThik82-/view?usp=sharing

css
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Drive lubing

Also, any recommendations on potentially what lube to use?  I've seen some repair videos utilizing lithium grease?

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Not familiar with those

Not familiar with those generic drives but if you have four drives doing the same thing I wonder whether your disk drive card is faulty? 

When you tried the Disk ][, do you hear the head "rattling" when the computer is powered up? 

Something like this, more or less: https://www.youtube.com/watch?v=-FJMojuU33g

 

I used silicon grease - in very small quantities. See this guide for directions: https://www.applefritter.com/appleii-box/H084_1_AppleIIDiskService1.htm

Clean everything with isopropyl alcohol and cotton buds first, then apply the grease as directed. That applies to the Disk ][ though. I do not see how the head is being moved from your videos. 

 

 For checking the speed you need to be able to boot a diagnostic software - On the Disk ][ you can also look at the flywheel and check that the relevant marks (50hx or 60hz) are stationary using a traditional incandescent bulb.

css
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I've got extra controller

I've got extra controller cards and have tried them with both pairs of drives but no change.

Yes, on my Disk ][ drives I can hear the head rattle on startup.  I've already replaced the SN74LS125 chip on each just to eliminate that. Now, I've ordered used replacement analog cards to see how that goes.

 

On the pair of generic drives, they don't make a head rattle on startup but I don't know if they would do that when working 100%.

 

I will pick up some lithium grease and try to lube the drives. It may not be worth diagnosing much further on the generic drives but I will keep at it with the Disk ][s and check the drive speed.

 

Thanks for your suggestions!

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It feels a bit weird that you

It feels a bit weird that you have 4 bad drives but if you also have different drive cards, it looks like they are indeed bad.

On the replacement, I wonder whether those two adjustments you have on it should really be re-adjusted for your mechanics? 

 

Here is where I cannot recommend further besides re-seating connectors and chips. Others with much more experience than me will surely help!

Good luck!

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I don't know the past history

I don't know the past history of this equipment (it was a Craigslist purchase) but, when I first got both sets of these drives, one of the Disk ][s worked for a brief period of time. It started making some noises and then stopped reading discs. I cleaned the head and it worked for a short while again before I got to where I am now. Normally, I just use my FloppyEmu but I have a lot of old original Softdisk disk floppies that I plan on transfering via ADTPro.

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You could try carefully

You could try carefully spinning the white/yellowish disk by hand, that should move the head towards the centre of the disk. Then power up the computer and see if the heads is correctly returned to the back of the unit. That should give you some assurance that the stepper motor driving the head is working.

 

Did you check the speed using an incandescent light? That should also give you assurance that the speed is roughly there.

 

Another thing to check is that - once the head has returned to home - the dot on the aforementioned disk is in the correct position. You will have to move out the analogue board to see that and I found that moving the head to home position by hand by spinning the plastic disk will give you a different final position than what the drive would do by itself so I would just let the drive reset the head, power off and then inspect.

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They look remarkably like a

They look remarkably like a set of Chinon drives I have.  I also have mental blank on the other brand...  anyway all the usual stuff, check the speed, clean the head, and you may find you need to adjust the alignment.  I have some issues with mine where one drive will read/write its own disks but thats it.  Also no knowing if the floppies are also marginal the written data not to last very long also.

 

On mine there's a "bolt" that runs parallel to the direction of head movement that controls alignment. I'll see if I can find the destructions I was given on attempting head alignment.  I haven't tried it myself. 

 

Spec

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