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HP Forum Archive 09

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9121 Disk Drive Problem
Message #1 Posted by Mike on 27 Dec 2002, 8:13 p.m.

I have three 9121 disk drives. Two of them seat disks just fine. But the third has some sort of physical block that will not let my disks be inserted.

I have determined that what is happening is that the metal cover is not being moved out of the way (opened). But my problem is that I can't even see any mechanism for opening it.

I have posted the description and provided some photos, in hopes that someone who is familar with these drives might be able to see what is wrong.

9121 Problem and photos


Re: 9121 Disk Drive Problem
Message #2 Posted by Ellis Easley on 30 Dec 2002, 5:51 p.m.,
in response to message #1 by Mike

I have read in HP manuals that HP's first 3.5" floppy diskettes had manually operated covers that you had to slide open before you insert the diskette into the drive. I believe this only applied to early single sided diskettes. I haven't actually read that early drives needed to use these manual diskettes, but the way HP concentrated on documentation back then, if the early drives needed manual diskettes, the drives would have come with documentation that spelled it out.

If this is the case and you have such an early drive, I guess you will have to remove the covers from some diskettes in order to use the drive.

Message #3 Posted by Mike on 31 Dec 2002, 1:25 a.m.,
in response to message #2 by Ellis Easley

That's it. You have it right. After you posted this, I did a search of the drives inside (OA-D30V). Don't know why I didn't think of that.

But I found this link specifically on the Sony OA-D30V drives.

Sony OA-D30V Drive (the first MicroDrive)

I had never heard of a manually opened disk. Maybe that was a Mac thing that didn't ever appear on PC or others. But, apparently some of the 9121 drives had this version.

So, what turned out to be a non-working drive, is actually one of the earlier models with a somewhat rare OA-D30V drive. I bet you can't find those special disks anywhere, though. Anyone else ever have this version of a 9121?

You can use the more modern 3.5" disks with 3 options.

1) Rip the cover off and use it without a cover.

2) Remove the spring and use it like the original.

3) Tape the cover open, and insert.

Of course the best way is to locate a stash of original Micro Floppydisks (OM-D30V).

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