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HP Forum Archive 19

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Update on my 9114 repairs in 2000
Message #1 Posted by Steve (Australia) on 8 Feb 2009, 9:41 a.m.

In September of 2000 I wrote this article http://www.hpmuseum.org/cgi-sys/cgiwrap/hpmuseum/articles.cgi?read=78 describing my 9114A repair journey.

I've recently looked around and found some references to my article and I am very flattered that people have considered it useful. I would like to complement whoever suggested isopropyl alcohol, and PeterP who has written a very useful reference.

A couple of months ago I tested the disk mechanism again and found it was gummed up again. Without thinking I pulled the disk out and immediately thought I had probably just ripped a head off it :-(

Anyway, someone got in contact with me regarding a problem with their 9114 and I thought it best to dive back into mine again before I risked theirs :-)

I searched and found a reference to using isopropyl alcohol, and having a spray bottle of it I gave it a shot. Well, 2 small squirts later (it probably helped that I knew where to squirt) the drive is ejecting again.

I have lubricated the drive again and I expect I'll have to repeat the process in another 7 years or so.

The good news is that because the drive had been stored with no disk in it, the heads had stuck up and out of the way, so I didn't need to bend heads back into shape again (lucky because my eyes are a hell of a lot worse than they were).

I guess I'm going to advise a couple things at this point:

1) if you have a 9114A, expect to have to do some maintenance every 5 to 10 years :-)

2) it may be best to store it without a disk in the drive.

3) if you do have a problem ejecting a disk, *don't* just pull it out.

My 9114B is still operating beautifully with no signs of any sticking.

The problem with the drive that was sent to me seems to have been simply that the battery was partially dead. I could say terrible things about how people treat their batteries, but mine was far "deader".

Since I've just replaced mine again (albeit with a smaller 1.3AHr battery that happened to be available on a Sunday afternoon in Perth) I am now considering how best to maintain it.

I'm not fond of the idea of leaving it permanently on charge as the potential for overcharge is real.

What I'm thinking of doing is leaving a charger on a mechanical timer set to charge the battery for (say) 30 minutes a week. Other than the actual time required (that I would adjust so that the charge does not slowly drop) can anyone think of any counter arguments or better solutions?

I'm probably going to do the same for my HP110 after I get the cells in that replaced.

NiCads are another issue. I'm sure that keeping them topped up is not the appropriate answer. I'm torn between using primary cells and making up packs using newer battery technology (NiMH, LiIon, LiFe, LiPo etc.) Any suggestions here?


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