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HP Forum Archive 02

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HP25: Some Keys with bad contact
Message #1 Posted by Jaime Tavares on 20 Mar 2000, 1:12 p.m.

Does anybody know how to repair bad contacts. There are some keys tha we must use much pressure. Thanks for any inputs.

      
Re: HP25: Some Keys with bad contact
Message #2 Posted by Frank Knight on 24 Mar 2000, 8:49 a.m.,
in response to message #1 by Jaime Tavares

I have had some success with stuffing a couple or few long strands of stainless steel soldering brush(avail Radio Shack in soldering tools) up into the contact area (plated through hole directly below key on keyboard and moving around circularly while pressing some on the keys,getting the strands between the contacts and over the edge of the PTH. This process done several times has gotten keys working that have formally not, as it does manage to scrub the contact area. Suggest you not overdo it, but it's worth a try before keyboard teardown, or keyboard replacement. Good luck, Frank

      
Re: HP25: Some Keys with bad contact
Message #3 Posted by Veli-Pekka Nousiainen on 8 Apr 2000, 7:28 p.m.,
in response to message #1 by Jaime Tavares

Hi !

It is quite possible that the contact between the halves of the calculator is crimped because of a twist in the case caused by an impact. Open the calc and look with a magnifying glass the contact pins. They should be a little bit separeted like a fork. If not then use a small screwdriver head to separate them. Now they should have a better contact to the "pipes" at the oppposite half of the calc. (I mean the top and bottom halves, by no means saw your calc into two halves ;-).


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