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HP Forum Archive 14

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HP45 Keys
Message #1 Posted by Paul Marin on 28 May 2004, 10:29 a.m.

Just some help on key board buttons. I have a HP45 unit which has some of its keys on the numberpad, which when depressed, dont make the "click" sound. They feel soft and dont confirm the keystroke. Any suggestions of what may have caused this and how to fix it if possible? I know someone at some stage asked the same question, but I can't backtrack and find the infomation. Thanking anyone for their help

Paul

      
Re: HP45 Keys
Message #2 Posted by David Smith on 28 May 2004, 12:44 p.m.,
in response to message #1 by Paul Marin

The key strips probably have cracks in them. Each row of key contacts is made of a thin stainless steel strip that is spot welded to the circuit board between each key. Best bet is to replace the keyboard with one from another unit. Next best is to remove the bad strips and replace them with ones salvaged from another unit (requires soldering). Worst fix is to attempt to fix the cracks with solder... it will break again very shortly.

      
Re: HP45 Keys
Message #3 Posted by Jon on 28 May 2004, 1:35 p.m.,
in response to message #1 by Paul Marin

Hi:

I have repaired one with excellent result. I used 0.5 mm. steel foil. It requires soldering, of course

            
Re: HP45 Keys
Message #4 Posted by David Smith on 28 May 2004, 4:23 p.m.,
in response to message #3 by Jon

Be aware that many types of stainless steel do not solder. The key strips the HP45 are usually gold plated. Those in the HP65/67/etc are not (but they solder just fine).


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