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HP Forum Archive 18

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HP-97 Keyboard Problem
Message #1 Posted by Nick Taylor on 4 Dec 2007, 8:55 p.m.

I finally managed to get a PSU for a HP-97 that someone gave me, and powered it on today.

It all worked, but had the gummy card reader. I managed to successfully fix this using instructions found on the Internet.

After I reassembled the unit, I noticed that the key "2" wasn't that responsive, and unless I pressed it hard, wouldn't register.

I disassembled the unit, and got to the contact strips and separator sheets and cleaned all the contacts with alcohol and reassembled.

This has been a disaster! Initially all the small keys on the left-hand keypad wouldn't work. So I disassembled the keyboard again and checked the copper strips and made minor adjustments. In short, I've not managed to get it working properly again, and I've made a mess of the copper contacts sheet. It's a pain having to reassemble the whole unit, to be able to test whether the keys are working.

Is there anywhere that I can buy a new contact sheet or keyboard?

Does anyone have the skill to fix this mangled sheet for me?

Do I have any other options?

I'm sickened as the card reader works very nicely! That bit I did well.



Re: HP-97 Keyboard Problem
Message #2 Posted by Randy on 4 Dec 2007, 9:24 p.m.,
in response to message #1 by Nick Taylor

The *only* place you'll ever find those replacement parts is from another 97.

So I disassembled the keyboard again and checked the copper strips and made minor adjustments

There are no "adjustments". None of any kind. It's contact sheet, spacer, spacer. Sounds like it was either previously assembled incorrectly, a fairly common problem or you didn't take good notes when disassembling. The entire process is explained with cut-away drawings in the service manual which can be obtained from the Museum.

If you installed it in any other order than contact, spacer, spacer that was the problem but for the life of me, I cannot understand how you could have damaged the contacts. Unless of course you took to actually bending things :(

If contacts were bent, what was bent would factor into the chances of repair. Bend the small U's on the ends of the leafs and I wouldn't be very hopeful of it ever being the same again.

Options? Buy another 97 and part it out.

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